OChem II - Ch. 12 and Spectroscopy
When determining the product formed from the sharpless epoxidation, the allylic alcohol is drawn in the plane w the OH group in the upper right corner. In this orientation, match the correct tartrate isomer w the orientation of epoxide addition.
(-)DET -> epoxidation ass oxygen from above the plane (+) DET -> epoxidation ass oxygen from below the plane
The most common organic oxidizing agent that contain metal-oxygen bonds contain either chromium in the __ oxidation state or manganese in the __ oxidation state
+6, +7
The most common organic oxidizing agents that contain metal-oxygen bonds contain either chromium in the _____ oxidation state or manganese in the _____ oxidation state.
+6, +7
The Sharpless reagent uses one of two different chiral reagents along with a titanium catalyst and tert-butyl hydroperoxide. What is the identity of the chiral reagents?
- (-)-diethyl tartrate - (+)-diethyl tartrate
Match each region of the IR spectrum to the correct wavenumber range: -functional group region -fingerprint region
- 4000-1600 cm^-1 - 1500-500 cm^-1
Which of the following options correctly describe the conversion of an alkene to an alkane?
- A C=C π bond is replaced by two C-H σ bonds. - This is a reduction reaction.
Which of the following options correctly describe the oxidation of primary alcohols?
- A carboxylic acid can be produced by oxidation of a primary alcohol. - Mild oxidizing conditions will result in an aldehyde product.
Which of the following options correctly describe an epoxidation reaction?
- A single oxygen atom is added across the double bond of an alkene in this type of reaction. - An alkene is reacted with a peroxyacid to give an epoxide.
Which of the following functional groups can be reduced by reaction with metal hydride reagents such as LiAlH4?
- Alkyl halides - Epoxides
Which of the following options correctly describe an asymmetric synthesis?
- An asymmetric synthesis produces predominantly or exclusively a single stereoisomer. - This type of synthesis makes use of a chiral reagent that favors the formation of one stereoisomer over another. - An asymmetric synthesis is enantioselective.
Which products could be produced by oxidative cleavage of an alkyne?
- CO2 - carboxylic acids
The oxides of ______ are commonly used as oxidizing agents in organic synthesis.
- Cr(VI) - Mn(VII)
Hydride reducing reagents such as NaBH4 and LiAlH4 provide the equivalent of H2 by adding _____ and _____ to the compound being reduced.
- H- ions - H+ ions
Which of the following options correctly describe the mechanism of hydrogenation of an alkene in the presence of a metal catalyst?
- H2 molecules are adsorbed onto the surface of the catalyst. - The catalyst complexes to the π bond of the alkene. - The H2 molecule is cleaved to form two H atoms, which can react with the alkene
Which of the following are the common TYPES of reducing agent used in organic chemistry?
- Hydride reducing agents - Molecular H2 - Dissolving metal reagents
Which of the following compounds could be produced by reacting an alkene with O3 followed by either Zn or CH3SCH3?
- Ketone - Aldehyde
Which of the following statements about the coenzyme NAD+ are correct?
- NAD+ is a biological oxidizing agent. - NAD+ converts an alcohol to a carbonyl compound.
From the following list, select all the reducing agents that are commonly used in organic reactions.
- NaBH4 - H2 with a metal catalyst - Na in NH3 (l)
The Lindlar catalyst is composed of Pd on a CaCO3 support. The metal is "poisoned" or made less reactive toward π bonds by the addition of _____ and _____.
- Pb(OAc)2 - quinoline
Which of the following steps are involved in anti dihydroxylation of an alkene?
- Reaction of an alkene with peroxyacid - Nucleophilic attack on an epoxide
Which of the following correctly identify the main types of oxidizing agents used in organic oxidation reactions?
- Reagents containing an oxygen-metal bond - Reagents containing an oxygen-oxygen bond
Which of the following options correctly describe the oxidation of secondary alcohols?
- Secondary alcohols can be oxidized by any Cr(VI) oxidizing agent. - Secondary alcohols are oxidized to form ketones.
Which of the following options correctly describe the relationship between the geometry of the starting alkene and the stereochemistry of the epoxide that it forms?
- The geometry of the alkene is retained in the epoxide due to syn addition. - The substituents in a cis alkene will still be cis in the epoxide.
Which of the following options correctly describe a dihydroxylation reaction?
- The product of this reaction may be called a glycol. - In this reaction an alkene is converted to a diol.
Which of the following options correctly describe the addition of H2 to an alkene?
- This reaction is a reduction reaction. - The product of this reaction is an alkane. - One hydrogen atom is added to each carbon atom of the double bond.
Which of the following substances are combined to make the Sharpless reagent?
- Ti catalyst - diethyl tartrate (+ or -) - (CH3)3COOH
Which of the following options describe the bonds broken and formed when an alkene is reduced to an alkane?
- Two σ bonds are formed. - One π bond is broken.
From the following list, select ALL reagents commonly used in organic oxidation reactions.
- acidic aq. Na2Cr2O7 - mCPBA - O3
Which of the following types of compounds can be produced by oxidation of an alcohol?
- aldehyde - ketone - carboxylic acid
Which of the following functional groups can be reduced by reaction with H2 and a metal catalyst?
- alkene - aldehyde - alkyne - ketone
Wh of the following options correctly describes an epoxidation rxn?
- an alkene is reacted w a peroxyacid to give an epoxide -a single o atom is added across the double bond of an alkene in this type of rxn
Which of the following classes of compounds can be produced by oxidation of a primary alcohol?
- carboxylic acid - aldehyde
Which of the following sets of reagents will result in syn dihydroxylation of an alkene?
- i) OsO4, ii) NaHSO3, H2O - KMnO4 in aqueous OH-
Select the variables that are plotted on the x and y axes in a mass spectrum
- m/z (mass to charge ratio) on the x-axis -abundance (intensity) on the y-axis
Describe how an IR spectrum can be used to determine functional group information.
- molecules that contain the same type of bonds will have similar IR spectra -different types of bonds vibrate at different frequencies
The IR absorption peak for an OH group _____
- occurs in the range 3600-3200 cm^-1 - is extremely broad and strong
Which of the following may be components of the Lindlar catalyst?
- quinoline - Pd/CaCO3 - Pb(OAc)2
Describe the steps in the process for analyzing an unknown organic compound using a combination of MS and IR data.
- the molecular mass is used to determine possible molecular formulas -the IR spectrum indicates what functional groups are most likely to be present
Describe the oxidation of ethanol by the enzyme alcohol dehydrogenase.
- the second step of the rxn produces the acetate anion as a product -if large quantities of ethanol are present the aldehyde can build up in this rxn -in the first step ethanol is oxidized to acetaldehyde
wavenumber =
- v bar -1/lambda -cm^-1
Wh of the following substances are combined to make the sharpless reagent?
-(CH3)3COOH -Ti catalyst (Ti[OCH(CH3)2]4) -diethyl tartrate (+/-) DET
Wh of the following options describe the bonds broken and formed when an alkene is reduced to an alkane?
-1 pi is broken -2 sigma are formed
Wh reagent sequence is typically used for oxidative cleavage of an alkyne?
-1) O3, 2) H2O
Wh of the following reagent combinations can be used in the oxidative cleavage of alkenes?
-1) O3; 2) CH3SCH3 -1) O3; 2) Zn, H2O
Wh of the following options describe an asymmetric synthesis?
-An asymmetric synthesis is enantioselective -An asymmetric synthesis produces predominantly or exclusively a single stereoisomer -This type of synthesis makes use of a chiral reagent that favors the formation of 1 stereoisomer over another
Wh structure shows the correct product for the reduction of the epoxide 2-epoxypropane, 1) LiAlH4, 2) H2O A. isobutanol, B tert-butanol, C. tert-butane, D. isopropanol
-B X not A bc the hydride ion will attack at the less sub C atom, leaving the OH on the more sub C atom
Wh products could be produced by oxidative cleavage of an alkyne?
-CO2 -carboxylic acids (CH3CH2COOH, CH3COOH can only be formed if the alkyne has a methyl group attached to the triple bond
Describe electrospray ionization mass spectrometry
-ESI ionizes the sample by creating a fine spray of charged droplets in an electric field -ESI can be used to record mass spectra for very large molecules
What are the steps involved in catalytic hydrogenation in chronological order?
-H2 absorbs to the catalyst surface -the pi bond of the alkene complexes with the metal -two H atoms are transferred sequentially to the pi bond -the alkane is released from the catalyst surface
Which of the following are oxidizing agents that contain an oxygen-oxygen bond? -PCC -H2O2 -O3 -NaBH3CN -Benzoyl peroxide
-H2O2 -O3 -benzoyl peroxide
Wh of the following describe a dihydroxylation rxn?
-In this rxn an alkene is converted to a diol -The product of this rxn may be called a glycol
Wh of the following sets of reagents will result in syn dihydroxylation of an alkene?
-KMnO4 in (aq) OH- -1) OsO4, 2) NaHSO3, H2O
Match each set of reagents w the correct stereo chemical outcome in the dihydroxylation rxn w a 1-methyl-pent-1-ene. A. 1-methyl-cis-1,2-dimethanol-pentane B. 1-methyl-trans-1,2-dimethanol-pentane
-KMnO4, OH- -> A (cis) -1) mCPBA, 2) OH- (trans)
Metal hydride reagents such as LiAlH4 contain a polar M-H bond. Match the partial charges to the correct group to show the polarity of the M-H bond. -M, H
-M -> partial + -H -> partial -
The oxides of _______ are commonly used as oxidizing agents in organic synthesis.
-Mn(VII) -Cr(VI)
Wh of the following options describe oxidizing agents containing Cr(+6) commonly used in organic rxns?
-Most Cr(+6) reagents require the presence of strong acids -K2Cr2O7, Na2Cr2O7, or CrO3 in (aq) acid -PCC is a selective oxidizing agent that can be used wo strong acid
Wh of the following statements about the coenzyme NAD+ are correct?
-NAD+ is a biological oxidizing agent -NAD+ converts an alcohol to a carbonyl comp
What are some examples of reducing agents?
-Na in NH3 -NaBH4 -H2 with a metal catalyst
What species are IR inactive?
-N≡N -O=O
What reagents are commonly used in organic oxidation rxns?
-O3 -acidic aq. Na2Cr2O7 -mCPBA
Wh of the following contain and O-O bond? -O3, NaBH3, Benslzoyl peroxide, H2O2, PCC
-O3, Benzoyl peroxide, H2O2
What reagents used for oxidizing alcohols is milder and more selective than others?
-PCC in CH2Cl2
Wh of the following reagents used for oxidizing alcohols is milder and more selective than others?
-PCC in CH2Cl2 (doesnt require strong acid) *CrO3, Na2Cr2O7, and K2Cr2O7 are strong and unselective in strong acid
wh of the following metals are commonly used together w H2 in catalytic hydrogenation? -Pd, Cu, Pt, Ni
-Pd, Pt, or Ni
Which of the following metals are commonly used together with H2 in catalytic hydrogenation? -Pt -Cu -Pd -Ni
-Pt -Pd -Ni
Wh of the following correctly identify the main types of oxidizing agents used in organic oxidation rxns?
-Reagents containing an O-metal bond -Reagents containing an O-O bond
Wh of the following steps are involved in anti dihydroxylation of an alkene?
-Rxn of an alkene w peroxyacid -Nucleophilic attack on an epoxide
Wh of the following option correctly describes the relationship bw the geometry of the starting alkene and the stereo chemistry of the epoxide that it forms?
-The geometry of all alkenes are retained in the epoxide due to syn addition -The substituents is a cis alkene will still be cis in the epoxide
Wh of the following statements is correct concerning the opening of an epoxide ring w HO- nucleophile?
-The nucleophile attacks from the back side of one of the C-O bonds -The result of the rxn is anti orientation bw the 2 hydroxyl groups
Wh of the following options correctly describe the addition of H2 to an alkene? -The product of this rxn is an alkane -this rxn is a reduction rxn -The rxn involves anti addition of H- & H+ to the C atoms -Both H atoms are added to the same C of the double bond -1 H is added to each C of the double bond
-The product of this rxn is an alkane -this rxn is a reduction rxn -1 H is added to each C of the double bond
Wh of the following correctly describe some of the disadvantages of conventional oxidizing agents?
-They produce carcinogenic by-products -many are toxic some reagents make use of corrosive acids
Ethanol, when ingested, is oxidized by NAD+ in the liver to what initial comp?
-acetaldehyde
Wh of the following rxns are used in the synthesis of the pheromone dispariure from acetylene? (17 parent chain, 6,7epoxy, 1methyl)
-acetylide substitution -> catalytic hydrogenation w lindlar catalyst -> epoxidation
What reagents are typically used in the oxidation of alcohols?
-acidic aq. K2Cr2O7 -CrO3 -PCC
Match each comp correctly to the product obtained on rxn w H2 and a metal catalyst. -aldeyde, ketone, alkene
-aldehyde -> 1° alcohol -ketone -> 2° alcohol -alkene -> alkane
Wh of the following functional groups can be reduced by rxn w H2 and a metal catalyst? -aldehyde, alcohol, alkyne, ketone, alkene
-aldeyde (product: 1° alcohol), alkyne, ketone, alkene (product: 2° alcohol)
Match each functional group the the correct oxidation product obtained from each. -alkenes, alkynes, alcohols
-alkenes -> diols (dihydroxylation), epoxides (epoxidation), or carbonyl compounds (oxidative cleavage; 2 products) -alkynes -> carboxylic acids (oxidative cleavage; 2 products) -alcohols -> aldehydes, ketones, or carboxylic acids (oxidative cleavage; 2 products)
Match each type of comp w the product that results from rxn LiAlH4, followed by (aq) workup -alkyl halide, epoxide
-alkyl halide -> alkane -epoxide -> alcohol
Describe an epoxidation rxn.
-an alkene is reacted with a peroxyacid to give an epoxide -a single oxygen atom is added across the double bond of an alkene in this type of rxn
Describe asymmetric synthesis.
-an asymmetric synthesis is enantioselective -makes use of chiral reagent that favors the formation of one stereoisomer over another -produces predominantly or exclusively a single stereoisomer
What are the steps involved in reduction of an alkyne to a trans alkene in chronological order?
-an electron adds to the triple bond to form a radical anion -the solvent NH3 supplies an H+ ion forming a radical intermediate -a carbanion is formed by the addition of an electron -protonation yields a neutral product
Organic oxidation often results in the replacement of C-H bonds with C-O bonds. Alcohols already contain a C-O bond, so oxidation of these compounds gives a product that conatains a(n) _______ functional group.
-carbonyl -carboxyl (only primary OH) -ketone (only secondary OH)
Organic oxidation often results in the replacement of C-H bonds w C-O bonds. Alcohols already contain a C-O bond, so oxidation of these comps gives a product that contains a(n) __ functional group.
-carbonyl -carboxyl (only primary alcohols; secondary will give a ketone)
Wh of the following types of comps can be produced by oxidation of an alcohol?
-carboxylic acid + aldehyde or ketone
Which substances are combined to make the Sharpless reagent?
-diethyl tartrate (+ or -) -Ti catalyst -(CH3)3COOH
What are the main factors that affect values of 13C chemical shifts?
-electronegativity of the atoms attached to the carbon -hybridization of the carbon atom
Match each type of heteroatom with its formula equivalence for the purpose of calculating the index of hydrogen: deficiency for a compound: -nitrogen -oxygen -halogen
-equivalent to an alkane having one fewer hydrogen (remove nitrogen from the formula along with a hydrogen) -equivalent to an alkane of the same formula (remove oxygen from the formula with no other change) -equivalent to a hydrocarbon having one more hydrogen (replace with a hydrogen in the formula)
Wh of the following are the common types of reducing agents used in ochem?
-hydride reducing agents (H+/-) - Mole. H2 (H-H) - Dissolving metal reagents (NaBH4 or LiAlH4)
Describe a dihydroxylation rxn.
-in this rxn an alkene is converted to a diol -the product of this rxn many be called a glycol
Describe electromagnetic radiation
-includes visible light -particles of ER exhibit wave behavior -the specific amount of energy a particular photon possesses is called a quantum
Select all the statements that correctly describe the effect of structure on the absorption of UV-visible light by a compound
-increasing conjugation causes λmax to shift to longer wavelengths -the greater the number of alkyl substituents on a double bond, the higher the value for λmax
The molecular ion produced when an organic molecule is bombarded by a high-energy stream of electrons ...
-is likely to fragment once formed -is a radical cation -shares the molecular mass of the compound
What are the expected IR absorptions for an alkene, what would help to distinguish its IR spectrum from that of an alkane or alkyne?
-medium peak at 1650 cm^-1 -medium peak at 3150-3000 cm^-1
Describe the oxidation of primary alcohols.
-mild oxidizing conditions will result in an aldehyde product -a carboxylic acid can be produced by oxidation of a primary alcohol
What are common types of reducing agents used in organic chemistry?
-molecular H2 -dissolving metal reagents -hydride reducing agents
Describe the bonds broken and formed wen an alkene is reduced to an alkane.
-one pi bond is broken -two sigma bonds are formed
Which of the following can readily be inferred simply from the molecular formula of an organic compound?
-possible number of multiple bonds and/or rings in the compound -possibility that the compound contains an odd number of N atoms
What are some examples of Lindlar catalysts?
-quinoline -Pd/CaCO3 -Pb(OAc)2
What steps are involved in anti dihydroxylation of an alkene?
-reaction of an alkene with peroxyacid -nucleophilic attack on an epoxide
What are the main types of oxidizing agents used in organic oxidation rxns?
-reagents containing an oxygen-metal bond -reagents containing and oxygen-oxygen bond
Describe the oxidation of secondary alcohols.
-secondary alcohols are oxidized to form ketones -secondary alcohols can be oxidized by any Cr(VI) oxidizing agent
Select all the statements that correctly describe the appearance of a 13C NMR spectrum
-signals do not exhibit spin-spin splitting in a typical 13C spectrum -the chemical shift of each signal gives information about the environment of each carbon atom -the number of signals indicates the number of different types of carbon atoms present
Which of the following statements is true regarding signal intensities in 13C NMR spectra?
-signals for C atoms with no H's attached are often less intense than other signals -signal intensities are not proportional to the number of C atoms causing the peaks
What are some disadvantaged of conventional oxidizing agents?
-some reagents make use of corrosive acids -many are toxic -they produce carcinogenic by-products
What factors determine the frequency at which a particular bond absorbs IR radiation?
-strength of the bond -mass of the atoms bonded
Select all the terms that correctly describe how structure affects 13C chemical shifts
-the C of a carbonyl group is usually the least shielded one in the 13C NMR spectrum -an sp2-hybridized C atom will give a signal farther downfield than an sp3-hybridized C atom -electronegative substituents attached to a C atom will increase the chemical shift
When using a combination of mass spectrometry and IR spectroscopy to determine the structure of an unknown compound...
-the IR spectrum identifies the possible functional groups present -the molecular formula should be used to determine the degrees of unsaturation
Describe how to correctly determine the product in a given sharpless epoxidation.
-the allylic alcohol should be drawn with the C=C bond horizontal and the -OH group in the upper right corner. -the alkene may need to be redrawn in order to place the -OH group in the conventional position.
Describe the behavior of an organic molecule in a mass spectrometer.
-the compound is bombarded by high-energy electrons, causing it to fragment -the organic molecule is ionized before fragmentation occurs
What could you assume if a compound with the chemical formula C6H8 reacting with H2/Pt to give a product with the formula C6H12.
-the compound must contain 1 ring -the hydrogenation data indicate the presence of 2 pi bonds
Describe the relationship between the geometry of the starting alkene and the stereochemistry of the epoxide that it forms.
-the geometry of the alkene is retained in the epoxide due to syn addition -the substituents in a cis alkene will still be cis in the epoxide
Describe a typical mass spectrum.
-the m/z values usually correspond to the masses of each fragment -the spectrum records the relative abundance for each m/z value -the tallest peak in the spectrum is called the base peak
Describe the typical mass fragmentation pattern for each type of compound?
-the major fragment for a hydrocarbon is the most stable carbocation possible -aldehydes and ketones fragment by alpha cleavage -alcohols often fragment by dehydration, leading to a loss of 18
Frenquency =
-the number of waves passing a point per unit time (v) -c/lambda -Hz or s^-1
Describe the addition of H2 to an alkene.
-the product of this rxn is an alkane -one hydrogen atom is added to each carbon atom of the double bond -this is a reduction rxn
Describe a typical mass spectrum
-the tallest peak in the spectrum is called the base peak -the spectrum records the relative abundance for each m/z value -the m/z values usually correspond to the masses of each fragment
Describe dissolving metal reductions.
-these rxns use an alkali metal like NA as a source of electrons -hydrogen is supplies in the form of H+ ions in this type of rxn.
What are some of the disadvantages of conventional oxidizing agents?
-they produce carcinogenic by-products -many are toxic -some reagents make use of corrosive acids
Describe the conversion of an alkene to an alkane.
-this is a reduction rxn -A C=C pi bond is replaced by two C-H sigma bonds
Describe the characteristics of an IR spectrum
-wavenumber (and frequency) decrease from left to right -peaks increase downward
Select all the statements that correctly describe the characteristics of an IR spectrum
-wavenumber (and frequency) decrease from left to right -peaks in an IR spectrum point downward -the spectrum is a plot of wavenumber versus percent transmittance
The presence of N atoms in a compound can sometimes be inferred from the molecular mass: for an even molecular mass:
-zero N atoms -even number of N atoms
What is the index of hydrogen deficiency of a compound with a molecular formula of C4H9N?
1 since N removes one H from C
Epoxidation is a reaction in which _____ oxygen atom(s) is/are added across a _____ bond to form an epoxide.
1, double
What is the IR spectrum wavenumber range for: 1.Functional group region & 2. Fingerprint region?
1. > or = to 1500 cm^-1 2. < 1500 cm^-1
Describe the typical fragmentation of an alcohol in mass spectrometry analysis
1. A peak of 18 mass units below the molecular ion peak is typical 2. alpha cleavage produces a resonance-stabilized carbocation 3. alcohols often fragment by alpha cleavage
Place the steps involved in reduction of an alkyne to a trans alkene in the correct order.
1. An e- adds to the triple bond to form a radical anion 2. The solvent NH3 supplies an H+ ion, forming a radical intermediate 3. A carbon ion is formed by the addition of an e- 4. -protonation yields a neutral product
Place the steps involved in catalytic hydrogenation in the correct sequence, starting with the first step at the top of the list.
1. H2 absorbs to the catalyst 2. The pi bond of the alkene complexes with the metal 3. Two H atoms are transferred sequentially to the sigma bond 4. The alkane is released from the catalyst surface
Place the steps involved in catalytic hydrogenation in the correct sequence.
1. H2 absorbs to the catalyst surface 2. The pi bond of the alkene complexes w the metal 3. 2 H atoms are transferred sequentially to the pi bond 4. The alkane is released from the catalyst surface
A compound w the chemical formula C6H8 reacts w H2/Pt to give a product a the formula C6H12. wh of the following correctly interpret this data?
1. [(2(6)+2)-8)]/2=3 total 2. [(2(6)+2)-12]/2=1 ring 3. 3-1= 2 pi -The hydrogenation data indicate the presence of 2 pi bonds -the comp must contain 1 ring
What will be the products of these reactants after undergoing oxidative cleavage? 1. terminal alkyne 2. internal alkyne 3. ethyne
1. one carboxylic acid and CO2 2. two carboxylic acids 3. CO2 only
Place the steps involved in the Cr(6+) oxidation of an alcohol in the correct order.
1. the alcohol OH group attacks the Cr atom of the oxidizing agent 2. proton transfer occurs, producing a chromate ester intermediate 3. An H atom attached to the C bearing the OH group is eliminated along w the Cr group
Loss of a methyl radical from a molecular ion during fragmentation in a mass spectrometer results in a peak ...
15 mass units lower than the mass or the original cation
other single bonds
1500 - 400 cm^-1
C=C
1650 cm^-1
Match each category of alcohol to its appropriate oxidation product. -1° -2° -3°
1° -> aldehyde or carboxylic acid 2° -> ketone 3° -> no rxn
In organic chemistry, all reducing agents provide the equivalent of _____ _____ atom(s) to the reaction.
2 hydrogen
Compound A, w molecular formula C7H10, reacts w H2/Pt to give compound B, with the formula C7H14. Compound A contains __ pi bonds and __ rings
2 pi bonds and 1 ring
double bonds
2000 - 1500 cm^-1
C≡C
2250 cm^-1
triple bonds
2500 - 2000 cm^-1
Each index of hydrogen deficiency in a compound represents a decrease of _____ hydrogens from the maximum possible for an alkane. To calculate the index of hydrogen deficiency for a hydrocarbon, subtract the number of _____ atoms in the formula from the number expected in a fully saturated hydrocarbon and divide by _____
2; hydrogen; 2
In ochem, all reducing agents provide the equiv of __ atoms to the rxn.
2H
C(sp3)-H
3000-2850 cm^-1
C(sp2)-H
3150-3000 cm^-1
C(sp)-H
3300 cm^-1
single bonds to hydrogen =
4000 - 2500 cm^-1
C-C
<1500 cm^-1
which of the compounds shown will give rise to the accompanying mass spectrum?
A
Wh 2 carbonyl comps are obtained after complete oxidative cleavage and reduction of the alkene 1-secpropylene-cyclohexane? A. ketone w methyl B. aldehyde w cyclohexane C. keton to cyclohexane D. keton w ethyl
A & C
C12 H16 O2
A particular ester has five degrees of unsaturation and gives a molecular ion in the mass spectrum at m/z = 192. Which of the following is the correct molecular formula of the compound? C12 H16 O2 C13 H18 O2 C13 H20 O C11 H16 N2 O
Match each starting material to the correct product/outcome in the reactions shown
A to E; B is no reaction; C to D
Select the correct structure for the product of the sharpless epoxidation, but-2-ene-ol, 1) (CH3)3COOH, 2) Ti catalyst + (-) DET
A. 2, 3-epoxy-butanol (front CH3) *(-) DET add O below the plane
Which alkene forms when the alkyne is reacted w/ H2 in the presence of a Lindlar catalyst? A. cis alkene B. trans alkene
A. cis alkene
_________ are compounds that contain a carbon-carbon triple bond
ALKYNES
c. vibrational
Absorption of IR radiation causes changes in the ____ motions of a molecule, causing its bonds to bend, stretch, and twist. a. rotational b. translational c. vibrational
b. narrow and weak/medium; broad and strong
Although NH and OH peaks occur in the same range of the IR spectrum, animes can readily be distinguished from alcohols by their IR spectra because the NH peak is ____, while the OH peak tends to be_____. a. broad and strong; narrow and medium/intense b. narrow and weak/medium; broad and strong c. broad and weak; broad and strong d. broad and strong; very weak
a. C7 H16 d. C6 H12 O
An organic compound is analyzed by mass spectrometry and found to have a molecular mass of 100. Which of the following are possible molecular formulas for this compound? a. C7 H16 b. C6 H15 N c. C5 H14 N2 d. C6 H12 O
c. C7 H17 N
An organic compound is analyzed by mass spectrometry and found to have a molecular mass of 115. Which of the following are possible molecular formulas for this compound? a. C8 H18 b. C7 H16 O c. C7 H17 N d. C6 H15 NO
a. increases, decreases
As the energy of a photon decreases, the wavelength ____ and the frequency ____. a. increases, decreases b. increases, increases c. decreases, decreases d. decreases, increases
b. decreases, increase Wavenumber is the reciprocal of wavelength
As the wavenumber for an IR absorption increases, the wavelength _____ while the frequency and energy both ____. a. decreases, decrease b. decreases, increase c. increases, decrease d. increases, increase
Wh alkene would form the epoxide 1,2-epoxybutane? A. prop-2-ene, B. prop-3-ene, C. cis-prop-2-ene
B
Rank the following alkenes in order of decreasing heat of hydrogenation. A. 2, 3-methyl-cyclopent-1-ene, B. 2-Methyl-1-ene-cylopentane, C. 1,2-Methyl-cyclopent-1-ene
B (di sub) > A (tri sub) > C (tetra sub)
Wh of the alkene will produce the desired alkane product when reacted w H2 in the presence of a metal catalyst? A. 3-isopropyll-1-butene, B. 2-methyl-2-butene, C. 2-methyl-1-butene, D. 2-methyl-3-butene
B, C, or D
wh of the following is the correct structure for the epoxide when the alkene, 1-methylene-cyclohexane, is reacted w mCPBA? A. 1,2-epoxy-1-methyl-cyclohexane B. 1-epoxy-cyclohexane C. cyclohex-oxy-ethane
B.
Why can a palladium (Pd) catalyst not be used to reduce an alkyne to an alkene?
Both π bonds will be reduced.
The mass spectrum of a compound containing one Br or one Cl will have two molecular ion peaks, at M and M+2. The ratio of the peaks reflects the relative abundance of the two isotopes. Match each halogen with the expected peak ratio for its molecular ion peaks: -Br -Cl
Br = 1:1 (two peaks of equal height) Cl = 3:1 (M has three times the intensity of M+2)
Ozonolysis of an alkene followed by reductive workup yields the 2 products; ketone & aldehyde w cyclohexane. wh option shows the correct structure for the original alkene? A. isopent-2-ene-cyclohexane B. isobut-2-ene-cyclohexane C. isobut-1-ene-cyclohaxane
C
which of the compounds shown will give rise to the accompanying mass spectrum?
C
which of the following cation fragments are most likely to be formed by characteristic fragmentation of the compound shown
C, D
Rank triple, double, and single bonds in order of increasing wavenumber for its IR absorption (lowest to highest)
C-C < C=C < C≡C
Select the correct structure for the product of the sharpless epoxidation, but-2-ene-ol, 1) (CH3)3COOH, 2) Ti catalyst + (+) DET
C. 2, 3-epoxy-butanol (back CH3) *(+) DET adds O above the plane
A particular ester has 5 degrees of unsaturation, and gives a molecular ion in the mass spectrum at m/z=192. Whats the correct molecular formula of the compound.
C12H16O2
Hydride reduction of the epoxide shown will result in nucleophilic attack by H- at the carbon marked __ and the product will be a(n) __.
C2; alcohol *H- attack occurs at the less sub C atom
An organic compound is analyzed by mass spectrometry and found to have a molecular mass of 115. Whats the molecular formula for this compound?
C7H17N
which products are produced by oxidative cleavage and aq. workup of the alkyne shown?
CH3CH2COOH, CO2
Wh products are produced by oxidative cleavage and aqueous workup of the alkyne 3-methyl-prop-1-yne, 1)O3, 2) H2O?
CH3Ch2COOH + CO2
which products could be produced by the oxidative cleavage of an alkyne
CO2 & carboxylic acid, not ketones or aldehydes
What products could be produced by oxidative cleavage of an alkyne?
CO2 & carboxylic acids
Wh of the options give the correct product of the alkyl halide, 3-methyl-bromo-cyclopentane, 1) LiAlH4, 2) H2O A. 3-methyl-cyclopentanol, B. 3-methyl-cyclopentene, C. 1, 2-dimethyl-cyclopentane, D. 1-methyl-cyclopentane
D
Which of the options gives the correct product for the reaction shown?
D
Which statement best describes a 1H-13C HETCOR NMR spectrum?
Each peak in the spectrum shows the direct attachment of a proton or a group of protons to a specific carbon atom
________ rxns form predominatley or exculsivley one enantiomer
Enantioselective
______ is the addition of a single oxygen atoms to an alkene to form an epoxide
Epoxidation
True or false: Hydrogenation allows direct determination of the degrees of unsaturation in a compound.
False
T/F Hydrogenation allows direct determination of the degrees of unsaturation in a compound.
False hydrogenation data indicate the number of pi bonds in a compound. unsaturation includes the presence of rings as well as pi bonds.
True or false: all COSY NMR spectra plot a 13C NMR spectrum of a molecule on the y-axis and its corresponding 1H NMR spectrum on the x-axis
False; a COSY spectrum plots 1H NMR spectra on both axes; the off-diagonal peaks contain information about the connectivity of the molecule
What method is useful for the routine analysis of the mixtures of compounds
GC-MS
__ chemistry is the use of environmentally benign methods to synthesize comps.
Green
b. more, higher Since H is small, Z-H bonds are strong and require more energy to vibrate. Stronger bonds require more energy for vibration. The greater the energy requires to vibrate the bond, the higher the frequency and wavenumber for the IR absorption.
H is the smallest of all elements; therefore single bonds to hydrogen require ____ energy to vibrate then single bonds to heavier elements. These bonds show characteristic IR absorptions with _____ wavenumbers. a. less, higher b. more, higher c. less, lower d. more, lower
Hydride reducing reagents such as NaBH4 & LiAlH4 provide the equiv of H2 by adding __ & __ to the comp being reduced.
H+ & H- ions
From the following list, select all the reducing agents that are commonly used in ochem.
H2 w a metal catalyst Na in NH3 (l) NaBH4 LiAlH4
What can be used as a green alternative to conventional oxidizing agents?
HCrO-4- & Amberlyst A-26 resin
Wh of the following measured quantities is commonly used as an indication of the relative stability of 2 related alkene? -Heat of hydration, heat of hydrogenation, boiling point, or relative density.
Heat of hydrogenation
Reducing agents such as NaBH4 and LiAlH4 are called _____ reducing agents because they deliver H- ions to the substrate.
Hydride
____________ of a terminal alkyne adds BH2 to the less substituted, terminal carbon
Hydroboration
Functional
IR spectroscopy is primarily used by organic chemists to identify the possible ____ groups in a compound.
Molecular Positive
In a mass spectrometer, an organic molecule will lose an electron to form the ____ ion or parent ion, which has a ____ charge and has the same molecular mass as the original compound.
a. electrons, cations
In a mass spectrometer, bombardment by a stream of high-energy _____ causes a molecule to fragment, forming a mixture of radicals and ions. The mass spectrometer analyzes the masses of the _____ only, giving a count of each mass fragment present. a. electrons, cations b. electrons, radicals c. protons, cations d. protons, radicals
____ tautomers have a C=C and an additional C-H bond
Keto
Which catalyst will result in the syn addition of only one equivalent of H2 across the triple bond of an alkyne, giving an alkene as the product?
Lindlar catalyst
Energy
Mass spectrometry, IR spectroscopy, and NMR spectroscopy are all techniques used to determine structures of organic molecules. Although each technique gives different information, all of them rely on the interaction of a(n) _____ source with a molecule to produce a change from which molecular information can be inferred.
Single bonds to hydrogen => 4000-2500 cm^-1 Triple bonds => 2500-2000 cm^-1 Double bonds => 2000-1500 cm^-1 Other single bonds => 1500-400 cm^-1
Match each bond type to the region of the IR spectrum where absorption would occur. Bond type: - Single bonds to hydrogen - Triple bonds - Double bonds - Other single bonds Wavelengths: - 2000-1500 cm^-1 - 1500-400 cm^-1 - 2500-2000 cm^-1 - 4000-2500 cm^-1
functional group region => ≥ 1500 cm^-1 fingerprint region => < 1500 cm^-1
Match each region of the IR spectrum to the correct wavenumber range. Regions: - functional group region - fingerprint region Range: - < 1500 cm^-1 - ≥ 1500 cm^-1
amine => sharp medium intensity peak(s) 3400-3200 cm^-1 amide => sharp medium intensity peak(s) 3400-3200 cm^-1 as well as strong peak at 1660 cm^-1 nitrile => medium/weak peak around 2250 cm^-1
Match each type of nitrogen-containing functional group with its expected IR absorption(s). Groups: amine, amide, and nitrile IR: - sharp medium intensity peak(s) 3400-3200 cm^-1 as well as strong peak at 1660 cm^-1 - sharp medium intensity peak(s) 3400-3200 cm^-1 - medium/weak peak around 2250 cm^-1
Frequency Functional
Molecular vibrations are quantized, which means that discrete vibrational energy states exist within a molecule. Each type of bond has its own specific vibrational modes, so that each type of bond vibrates at a different ______. This leads to specific absorption peaks in the IR spectrum for each different _____ group present in the molecule.
c. This peak arises due to the presence of carbon-13 isotopes in the molecule
Most mass spectra show a small peak at 1 mass unit amor the molecular mass of the compound. How does this peak arise? a. This peak arises due to a small percentage of molecules that gain a mass unit during the initial ionization process. b. This peak reflects the presence of carbon-14 isotopes in the molecule c. This peak arises due to the presence of carbon-13 isotopes in the molecule
Wh reagent will facilitate anti addition of H2 across a triple bond to give a trans alkene?
Na in (l) NH3
Which reagent will facilitate anti addition of H2 across a triple bond to give a trans alkene?
Na in liquid NH3
Dissolving metal reductions w sodium (Na) and ammonia (NH3). These reductions use __ as the source of electrons and __ as the source of protons.
Na; NH3
What reagent sequence is typically used for oxidative cleavage of an alkyne
O3 & H2O
A dihydroxylation rxn is one in which two _____ groups are added to adjacent atoms of a C=C double bond. The product of the rxn is called a(n)_______.
OH / 1,2-diol
A dihydroxylation reaction is one in which two _____ groups are added to adjacent carbon atoms of a C=C double bond. The product of the reaction is called a(n) _____.
OH, 1,2-diol
A dihydroxylation rxn is one wh 2 __ groups are added to adj carbon atoms of a C=C bond. The product of the rxn is called a(n) __.
OH; 1, 2-diol
Match each oxidation product to the correct set of reagents in the rxn: butanol. A. propyl-aldehyde B. propyl- carboxylic acid
PCC in CH2Cl2 -> A K2Cr2O7 in (aq) H2SO4 -> B
Wh of the following may be components of the Lindlar catalyst? Pt, quinoline, Na/NH3, Pd/CaCO3, Pb/(OAc)2
Pd/CaCO3 -The Pd catalyst is poisoned w/ Pb/(OAc)2 or quinoline
Match each structure to its description. A. contains O-OH B. contains C-OOH
Peroxide = B Peroxyacid = A
X-ray UV radiation Visible light IR radiation Radio waves
Place the following types of electromagnetic radiation in order of increasing wavelength. Radio waves X-ray IR radiation Visible light UV radiation
What type of information is provided by the IR spectrum of an organic compound?
Possible identity of functional groups present
Which of the following changes in energy state will result in the absorption of light in the UV-visible range of the electromagnetic spectrum?
Promotion of an electron from a lower electronic energy state to a higher one
The Lindlar catalyst is composed of Pd on a CaCO3 support. The metal is "poisoned" or made less reactive toward pi bonds by the addition of______ and ______.
Quinoline & Pb(OAc)2
The reaction that allows enantioselective synthesis of epoxides is called the _______ epoxidation.
Sharpless
The rxn that allows enantioselective synthesis of epoxides is called the ____________ eposidation.
Sharpless
______ are constitutional isomers that differ in the location of a double bond and a hydrogen and exist in an equilibrium with each other
Tautomers
In what way does the sharpless reagent control the stereochemical outcome of the sharpless epoxidation?
The DET isomer blocks one face of the alkene, and the stereochemistry of the DET determines wh face is blocked
b. is extremely broad and strong d. occurs in the range 3600-3200 cm^-1
The IR absorption peak for an OH group ____. Select all that apply. a. is found at 1800 cm^-1 on the spectrum b. is extremely broad and strong c. is a narrow, intense peak d. occurs in the range 3600-3200 cm^-1 e. tends to be a very weak absorption
d. lower, downward
The IR spectrum is a plot of frequency/wavenumber vs. % transmittance. The greater the amount of radiation absorbed by the sample, the _____ the % transmittance so that peaks in the spectrum increase ____ on the spectrum. a. lower, upward b. higher, downward c. higher, upward d. lower, downward
Nitrogen Odd
The ____ rule reflects the fact that an odd number of nitrogen atoms in a compound causes the compound to have an ____ molecular mass.
Select the statement that correctly describes the interaction of a molecule with IR radiation
The bonds of the molecule vibrate in various ways
The mass spectrum of a given organic compound shows three clusters of peaks at m/z values of 155/157, 183/185, and 198/200. In each cluster, the lower mass peak is about three times more intense than the higher mass peak. Which of the following structural features would account for this observation?
The compound contains a Cl atom
c. directly, high, short
The energy of a photon is ____ proportional to its frequency. A high-energy photon has a ____ frequency and a ____ wavelength. a. directly, low, long b. inversely, high, short c. directly, high, short d. directly, high, long
Two 2
The halogens Br and Cl each have two naturally occurring isotopes of high abundance. The mass spectrum of a compound containing one BR or one Cl atom will show TWO molecular ion peaks that are _____ mass units apart, at M and M + ____.
c. lower, smaller Wavelength is inversely proportional to both energy and frequency.
The longer the wavelength of energy absorbed by a molecule, the ____ the frequency of the energy and the ___ the energy difference between the two energy states in the molecule. a. higher, greater b. lower, greater c. lower, smaller d. higher, smaller
d. weaker, lower
The lower the % s-character of a bond, the ____ the bond and therefore the _____ the wavenumber for its IR absorption. a. stronger, lower b. stronger, higher c. weaker, higher d. weaker, lower
b. mass-to-charge ratio
The mass spectrometer detects and analyzes the cations produced by fragmentation of an organic molecule. The analyzer determines the _____ for each fragment. a. vibrational frequency b. mass-to-charge ratio c. mass-to-volume ratio d. mass
a. is a graph of the abundance of each cation plotted against its m/z value, which typically equals its mass.
The mass spectrum _________. a. is a graph of the abundance of each cation plotted against its m/z value, which typically equals its mass. b. records the amount of energy absorbed by each fragment c. records the abundance of each cation fragment plotted against its relative reactivity
Select the statement that correctly describes the information recorded in a mass spectrum
The mass spectrum is a graph of the abundance of each cation plotted against its m/z value, which typically equals its mass
a. is likely to fragment once formed b. shares the molecular mass of the compound d. is a radical cation
The molecular ion produced when an organic molecule is bombarded by a high-energy stream of electrons ____. Select all that apply. a. is likely to fragment once formed b. shares the molecular mass of the compound c. is negatively charged d. is a radical cation e. is highly stable
b. strength, mass Note: Where a particular bond absorbs in the IR depends on bond strength and atom mass. - Bond strength: stronger bonds vibrate at higher frequency, so they absorb at higher wavelengths - Atom mass: bonds with lighter atoms vibrate at higher frequency, so they absorb at higher wavelengths
The specific frequency of IR radiation absorbed by a particular bond depends on the _____ of the bond and the _____ of the bonded atoms. a. polarity, electronegativity b. strength, mass c. strength, electronegativity d. polarity, masses
a. greater, higher
The stronger the bond between atoms, the ____ the amount of energy required to make the bond vibrate and the ___ the wavenumber at which the IR absoprtion will appear. a. greater, higher b. lower, lower c. lower, higher d. greater, lower
C - C C = C C (triple bond) C
The stronger the bond, the higher the frequency of vibration. Rank the following bonds in order of increasing wavenumber for its IR absorption. C (triple bond) C C - C C = C
Why does dissolving metal reduction of an alkyne yield exclusively the trans alkene product?
The vinyl carbonation intermediate is more stable with the bulky groups on opposite sides of the double bond.
Which of the following options correctly describe all reducing agents in organic chemistry?
They provide the equivalent of 2 H atoms to the reaction.
Most mass spectra show a small peak at one mass unit above the molecular mass of the compound. Select the statement that correctly explains the origin of this M+1 peak
This peak arises due to the presence of carbon-13 isotopes in the molecule
d. inversely, decrease
Wavelength and frequency are ____ proportional to each other. As wavelength increases frequency will ____. a. directly, decrease b. directly, increase c. inversely, increase d. inversely, decrease
d. the bonds of the molecule vibrate in various ways
When a molecule interacts with IR radiation _____. a. the bonds of the molecule break b. the molecules become aligned with the radiation c. the molecule rotates in various ways d. the bonds of the molecule vibrate in various ways
d. the bonds of the molecule vibrate in various ways
When a molecule interacts with IR radiation, ____. a. the molecule rotates in various ways b. the molecules become aligned with the radiation c. the bonds of the molecule break d. the bonds of the molecule vibrate in various ways
b. A heavier atom reduces the overall energy required for vibration; therefore the IR absorption for heavier atoms occurs at a lower frequency
When comparing the IR absorption of two similar bonds, which of the following correctly describes the effect of atomic mass on the frequency of absorption? a. A heavier atom requires more energy to make it vibrate; therefore the IR absorption for a heavier atom is at a higher frequency b. A heavier atom reduces the overall energy required for vibration; therefore the IR absorption for heavier atoms occurs at a lower frequency c. A heavier atom reduces the overall energy of vibration; therefore the IR absorption for heavier atoms occurs at a higher frequency d. A heavier atom requires more energy to make it vibrate; therefore the IR absorption for a heavier atom is at a lower frequency
b. the IR spectrum identifies possible functional groups present d. the IR spectrum should be used to determine the degrees of unsaturation
When using a combination of mass spectrometry and IR spectroscopy to determine the structure of an unknown compound ____. Select all that apply. a. the IR spectrum gives the molecular formula b. the IR spectrum identifies possible functional groups present c. the IR spectrum indicates how the different functional groups are connected d. the IR spectrum should be used to determine the degrees of unsaturation
A would show a broad, strong peak at 3500 - 2500 cm^-1 for the OH group
Which feature of an IR spectrum could easily be used to distinguish the two isomeric compounds from each other? (A: R - OOH & B: R - OO)
c. Mass spectroscopy
Which of the following analytical techniques is used primarily for determination of the molecular mass and molecular formula of an organic compound? a. UV spectroscopy b. IR spectroscopy c. Mass spectroscopy d. NMR spectroscopy
a. medium peak at 1650 cm^-1 c. medium peak at 3150-3000 cm^-1
Which of the following are the expected IR absorptions for an alkene, which would help to distinguish its IR spectrum from that of an alkane or alkyne? Select all that apply. a. medium peak at 1650 cm^-1 b. strong peak at 3000-2850 cm^-1 c. medium peak at 3150-3000 cm^-1 d. strong peak at 1800 cm^-1
d. There must be a change in dipole moment during the vibration.
Which of the following conditions must be fulfilled for a bond to absorb IR radiation? a. There must be both bending and stretching during the vibration b. There must be either bending or stretching during the vibration, but not both. c. There must be no change in dipole moment during the vibration. d. There must be a change in dipole moment during the vibration.
The energy of the absorbed photon must match the difference in the two energy states in the molecule
Which of the following correctly describes how energy is absorbed by a molecule? - The energy of the absorbed photon must exceed the difference in the two energy states in the molecule - The energy of the absorbed photon must match the difference in the two energy states in the molecule - The molecule will keep absorbing more photons until their combined energy equals the difference between the two energy states in the molecule
The specific amount of energy a particular photon possesses is called a quantum. Particles of electromagnetic radiation exhibit wave behavior. Electromagnetic radiation includes visible light. Note: A particle of electromagnetic radiation is called a photon.
Which of the following options correctly describe electromagnetic radiation? Select all that apply. - The specific amount of energy a particular photon possesses is called a quantum. - A particle of electromagnetic radiation is called a quantum. - Particles of electromagnetic radiation exhibit wave behavior. - Electromagnetic radiation includes visible light. - All electromagnetic radiation has the same frequency.
The IR spectrum indicates what functional groups are most likely to be present The molecular mass is used to determine possible molecular formulas
Which of the following options correctly describe steps in the process for analyzing an unknown organic compound using a combination of MS and IR data? - The molecular formula can be used to identify functional groups in the molecule - The IR spectrum indicates what functional groups are most likely to be present - The molecular mass is used to determine possible molecular formulas - The IR spectrum gives a clear indication of the molecular formula of the compound
c. The molecular mass is used to determine possible molecular formulas d. the IR spectrum indicates what functional groups are most likely to be present
Which of the following options correctly describe steps in the process for analyzing an unknown organic compound using a combination of MS and IR data? Select all that apply. a. The IR spectrum gives a clear indication of the molecular formula of the compound b. The molecular formula can be used to identify functional groups in the molecule c. The molecular mass is used to determine possible molecular formulas d. the IR spectrum indicates what functional groups are most likely to be present
The compound is bombarded by high-energy electrons, causing it to fragment The organic molecule is ionized before fragmentation occurs. Note: The sample is not exposed to any form of radiation in this technique. A high-energy stream of electrons ionizes the molecule, which then fragments. The fragments are sorted by mass and charge in a magnetic field.
Which of the following options correctly describe the behavior of an organic molecule in a mass spectrometer? Select all that apply. - High-energy electrons add to the organic molecule, forming a radical anion - Mass spectrometry is usually carried out in aqueous solution. - The compound is bombarded by high-energy electrons, causing it to fragment - The organic molecule is ionized before fragmentation occurs. - This technique involves analysis of the molecular fragments using radiation in the radiofrequency range.
a. Wavenumber (and frequency) decrease from left to right. d. peaks in an IR spectrum increase downward
Which of the following options correctly describes the characteristics of an IR spectrum? Select all that apply. a. Wavenumber (and frequency) decrease from left to right. b. Wavelength decreases from left to right c. The spectrum is a plot of wavenumber vs. % absorption d. peaks in an IR spectrum increase downward
Molecular mass Molecular formula
Which of the following options correctly identify the principal information that can be obtained from a mass spectrum of an organic compound? Select all that apply. - Definitive solution of C-H framework of molecule - Identification of functional groups - Molecular mass - Molecular formula
a. N (triple bond) N e. O = O
Which of the following species are IR inactive? Select all that apply. a. N (triple bond) N b. C-Cl4 c. C-O2 d. H2O e. O = O
A compound has a λmax in the violet region of the visible light range. What color does the compound appear?
Yellow
Wh of the following symbols, placed above a rxn arrow, indicate an oxidation rxn?
[O]
What symbol places above a rxn arrow indicates an oxidation rxn?
[O]
GCMS is a useful technique for collecting MS data when analyzing
a mixture of compounds or an impure compound
The reagent typically used to form an epoxide from an alkene is _____.
a peroxyacid
Epoxidation with the Sharpless reagent (-)-DET adds an oxygen atom from _____ the plane, while (+)-DET adds an oxygen atoms from ______ the plane
above / below
The amount of UV-VIS radiation absorbed by a sample is called its _____ (symbol A). This quantity will be affected by the _____ length of the radiation and the _____ of the sample. Correction for the variables gives ε = A / (c*l), which is called the molar _____ of the sample
absorbance; path; concentration; absorptivity
_________ anions are strong nucleophiles that open epoxide rings by an SN2 mechansism
acetylide
An asymmetric rxn is one that converts a(n) __ starting materials into predominantly __.
achiral; 1 enantiomer
An asymmetric reaction is one that converts a(n) ______ starting materials into predominantly ______.
achiral; one enantiomer
The base peak in the mass spectrum of a ketone or aldehyde is often due to a alpha-fragmentation, or cleavage of the bond adjacent to the carbonyl group. This cleavage yields a(n) ________ ion, which has a high abundance bc it is ________ stabilized
acylium / resonance
Which of the following compounds could be produced by reacting an alkene with O3 followed by either Zn or CH3SCH3?
aldehyde & ketone
Wh of the following classes of comps can be produced by oxidation of a primary alcohol?
aldehyde (by PCC) & carboxylic acid (by 1)K2C2O7, 2) H2SO4, H2O)
Oxidation of a primary alcohol w PCC will produce a(n) __; stronger Cr(6+) reagents rare necessary to produce a(n).
aldehyde or ketone; carboxylic acid
Primary alcohols are oxidized to ______ under milder rxn conditions, such as using PCC in CH2CL2
aldehydes
________ are formed from terminal alkynes with the addition of water using BH3 then H2O2
aldehydes
What type of compounds typically undergo alpha-cleavage in a mass spectrometer?
aldehydes, ketones, and alcohols
HCrO4- Amberlyst A-26 resin serves as green oxidant, oxidizing primary alcohols to __ and secondary alcohols to __.
aldehydes; ketones
Reduction of an alkyl halide such as CH3CH2Br with LiAlH4 will produce a(n) ______.
alkane
What type of compound is produced when an alkyne reacts with two equivalents of H2?
alkane
alkene
alkane
when an alkyne reacts w/ 2 equivalents of H2 an __ is produced.
alkane
Reduction of an alkyne with H2 and a Pd catalyst will always produce a(n) _________ as the product beacause the catalyst is highly reactive toward _____ bonds.
alkane / pi
Reduction of an alkyne with H2 and a Pd catalyst will always produce a(n)______ as the product because the catalyst is highly reactive toward _____ bonds.
alkane, pi
The reduction of an alkyne will produce an __ or an __ as the product.
alkane; alkene (cis/trans)
The reduction of an alkyne will produce either a(n)_______ or a(n)_____ as the product.
alkene or alkane
The reduction of an alkyne will produce either a(n)_____ or a(n)______ as the product.
alkene, alkane
The sharpless epoxidation is an enantioslective rxn that oxidizes alkenes to epoxides; however, only the double bonds of _______ alcohols are oxididized in this rxn.
allylic
The starting material for the Sharpless epoxidation is a(n) _____
allylic alcohol
The starting material for the sharpless epoxidation is a(n) __.
allylic alcohol
Which of the following is an appropriate substrate for a Sharpless epoxidation?
allylic alcohol
Wh of the following is an appropriate substrate for a sharpless epoxidation?
allylic alcohol (an alcohol having a hydroxyl group on the C adj to a C=C)
In analysis by mass spectrometry, amines tend to fragment by _____, which produces a resonance-stabilized carbocation
alpha cleavage
In analysis by mass spectrometry, aldehydes and ketones prefer to fragment by ______, which produced a resonance-stabilized acylium ion.
alpha-cleavage
Reduction of an alkyne with Na metal in liquid NH3 results in _____ addition of the elements of H2 across the triple bond and a _____ alkene is produced.
anti, trans
Why are tertiary alcohols not readily oxidized?
bc a tertiary alcohol has no H atoms on the C bearing the OH group
C-O group
below 1500 cm^-1
Why can a palladium (Pd) catalyst not be used to reduce an alkyne to an alkene?
both pi bonds will be reduced
OH group
broad peak 3600-3200 cm^-1
When the molecular ion consists of two peaks (M and M+2) in a 1:1 ratio, a ______ atom is present in the molecule.
bromine
Organic oxidation often results in the replacement of C-H bonds with C-O bonds. Alcohols already contain a C-O bond, so oxidation of these compounds gives a product that contains a(n) _____ functional group.
carbonyl
Oxidative cleavage of an alkene breaks both the sigma and pi bonds of the double bonds to form 2 new comps, each of wh contains a(n) __ group
carbonyl
Oxidative cleavage of an alkene breaks both the σ and the π bonds of the double bond to form two new compounds, each of which contains a(n) _____ group.
carbonyl
What classes of compounds can be produced by oxidation of a primary alcohol?
carboxylic acids & aldehydes
When the molecular ion consists of two peaks (M and M+2) in a 3:1 ratio, a _______ atom is present in the molecule.
chlorine
The structural unit associated with an electronic transition in UV-VIS spectroscopy is call a(n)
chromophore
During the reduction of an alkyne, adding 1 equivalent of H2 in a syn fashion forms a ____ alkene.
cis
The alkenes cis-3-hexene and trans-3-hexene are reacted w mCPBA. Match each alkene to the correct description of the epoxide group.
cis-3-hexene -> achiral meso comp trans-3-hexene -> racemic mixture (enantiomers)
A typical 13C NMR spectrum does not show spin-spin splitting because the C spins are deliberately _____ from the H spins to reduce the complexity of the spectrum
decoupled
Reduction results in an ______ of C-Z bonds, and a _______ in C-H bonds.
decrease, increase
As the number of conjugated π bonds in a compound increases, the HOMO-LUMO energy gap will _____, and the compound will absorb light of _____ wavelengths
decrease; longer
As the wavenumber for an IR absorption increases, the wavelength __________ while the frequency and energy both _______
decreases / increase
As the wavenumber for an IR absorption increases, the wavelength _____, and the frequency and energy both _____
decreases; increase
Unsaturated fats and oils can be partially hydrogenated with H2, reducing the ______.
degree of unsaturation
Unsaturated fats and oils can be partially hydrogenated w H2, reducing to the __
degrees of unsaturation or pi bonds
___________ is the addition of two hydroxy groups to a double forming, a 1,2-diol or glycol.
dihydroxylation
The energy of a photon is _____ proportional to its frequency. A high-energy photon has a ______ frequency and a _______ wavelength
directly / high / short
The energy of a photon is ______ proportional to its frequency. A high-energy photon has a ______ frequency and a ______ wavelength.
directly / high / short
Partially hydrogenated oils are those that have been reacted with H2 in the presence of a metal catalyst to reduce the number of C-C ______ bonds in the structure.
double
An enantioselective reaction affords a product that is predominately or exclusively a single ______ .
enantiomer
An enantioselective rxn affords a product that is predominately or exclusively a single __
enantiomer
A reaction that produces mostly or entirely one enantiomeric product is called a(n) _____ reaction.
enantioselective
A rxn that produces mostly or entirely one enantiomeric product is called a(n) _________ rxn.
enantioselective
The Sharpless epoxidation is an asymmetric reaction that allows ________ synthesis of epoxides.
enantioselective
In a mass spectrometer, a sample of organic molecules is vaporized and bombarded by a stream of high-_____ electrons. This causes a(n) _____ to be dislodged from the molecule, producing a cation called the _____ ion. This cation _____ further, forming smaller radicals and cations
energy; electron; molecular; dissociates
______ tautomers have an O-H group bonded to a C=C
enol
Anti dihydroxylation is achieved in two steps: __________ followed by opening of the ring with HO- or H2O
epoxidation
Anti dihydroxylation involves two steps, first the formation of a(n) _____ followed by _____ attack under either acidic or basic conditions.
epoxide, nucleophilic
Anti dihydroxylation involves 2 steps, 1st the formation of an __ followed by __ attack under either acidic or basic conditions.
epoxide; nucleophilic (resulting in diol enantiomers)
Which functional groups can be reduced by a rxn with metal hydride reagents such as LiAlH4?
epoxides & alkyl halides
Hydrocarbons and compounds that only contain C, H, and O atoms always have a molecular ion with an ________ mass.
even
Molecular vibrations are qunatized, which means the discrete vibrational energy states exist within a molecule. Each type of bond has its own specific vibrational modes, so that each type of bond vibrated at a different __________. This leads to specific absorption peaks in the IR spectrum for each different _________ group present in the molecule.
frequency / functional
Molecular vibrations are quantized, which means that discrete vibrational energy states exist within a molecule. Each type of bond has its own specific vibrational modes, so that each type of bond vibrates at a different _____. This leads to specific absorption peaks in the IR spectrum for each different _____ group present in the molecule
frequency; functional
IR spectroscopy is primarily used by organic chemists to identify the possible ______ groups in a compound
functional
IR spectroscopy is primarily used by organic chemists to identify the possible _____ _____ in a compound
functional groups
The stronger the bond btwn atoms the ______ the amount of energy required to make the bond vibrate and the _____ the wavenumber at which the IR absorption will appear.
greater / higher
_______ chemistry is the use of environmentally benign methods to synthesize compounds.
green
Which of the following measured quantities is commonly used as an indication of the relative stability of two related alkenes?
heat of hydrogenation
mass data for an organic compound that can provide a molecular mass to 4 decimal places or more is called _________ - ___________ mass spectrometry
high-resolution
The higher the percent s-character, the strong the bond, and the _________ the wavenumber of an IR absorption.
higher
reducing agents such as NaBH4 & LiAlH4 are called __ reducing agents bc they deliver H- ions to the substrate.
hydride
The index of _____ deficiency is calculated from the molecular formula of a compound. This gives information about the possible number of _____ bonds and/or _____ in the compound
hydrogen; multiple; rings
Which of the following reagent combinations can be used in the oxidative cleavage of alkenes?
i) O3; ii) Zn, H2O i) O3; ii) CH3SCH3
If Z is a more electronegative element than C, oxidation of an organic compound results in a(n) _____ in the number of C-Z bonds, while reduction results in a(n) _____ in the number of C-Z bonds.
increase, decrease
Oxidation results in an ______ of C-Z bonds, and a _______ in C-H bonds.
increase, decrease
As the energy of a photon decreases, the wavelength _____ and the frequency _____
increases / decreases
The _____ of hydrogen deficiency for a compound indicates the number of possible multiple bonds and/or rings present. Rings are distinguished from double bonds using hydrogenation data. A compound will consume _____ mole(s) of H2 (g) for every 1 mole of double or π bonds present
index; 1
Organic chemists use _____ _____ to identify the functional groups in a compound.
infrared spectroscopy
Wavelength and frequency are _____ proportional to each other. As wavelength increases frequency will _______
inversely / decrease
Oxidation of a secondary alcohol produces a(n) __
ketone
Oxidation of a secondary alcohol produces a(n) _____.
ketone
Oxidation of a secondary alcohol produces a(n)_______
ketone (R=O=R)
When an unsymmetrical epoxide reacts with LiAlH4, the hydride nucleophile attacks the ______ substituted carbon atom, so that the product will have the OH group on the _____ substituted carbon atom.
less / more
During catalytic hydrogenation, sterically crowded alkenes will complex _____ easily to the metal catalyst and hydrogenation will therefore occur at a ______ rate.
less / slower
When an unsymmetrical epoxide reacts with LiAlH4, the hydride nucleophile attacks at the _____ substituted carbon atom, so that the product will have the OH group on the _____ substituted carbon atom.
less, more
The longer the wavelength of energy absorbed by a molecule, the _______ the frequency of the energy and the ________ the energy difference btwn the two energy states in the molecule.
lower / smaller
The IR spectrum is a plot of wavenumber versus percent transmittance. The greater the amount of radiation absorbed by the sample, the _____ the percent transmittance so that peaks in the spectrum point _____ on the spectrum
lower; downward
A technique used for measuring the molecular weight and determining the molecular formula of an organic molecule is _________
mass spectrometry
The mass spectrometer detects and analyzes the cations produced by fragmentation of an organic molecule. The analyzer determines the _______ for each fragment.
mass-to-charge ratio
The mass spectrometer detects and analyzes the cations produced by fragmentation of an organic molecule. The analyzer determines the m/z (mass-to-charge) ratio for each fragment, where m represents the _____ and z represents the _____ of the cation. The value of z is almost always +1, so the m/z ratio is usually equal to the actual _____ of each individual ion
mass; charge; mass
nitrile (R−C≡N)
medium/weak peak around 2250cm^-1
Alkenes readily undergo hydrogenation by reaction with H2 in the presence of _____.
metal catalyst
In order for an alkene to react w H2, wh 1 of the following reagents or rxn conditions is required?
metal catalyst
In order for an alkene to react with H2, which one of the following reagents or reaction conditions is required?
metal catalyst
Reductions w molecular hydrogen (H2) occur on the surface of a(n) __.
metal catalyst
_____ _______ are formed from terminal alkynes with the addition of water using H2SO4 and HgSO4
methyl ketones
In a mass spectrometer an organic molecule will lose an electron to form the _______ ion or parent ion, which has a __________ charge and has the same molecular mass as the original compound.
molecular / positive
What principal information can be obtained from a mass spectrum of organic compounds?
molecular mass & molecular formula
H is the smallest of all elements; therefore single bonds to hydrogen require ______ energy to vibrate than single bonds to heavier elements. These bonds show characteristic IR absorptions with ______ wavenumbers.
more / higher
During catalytic hydrogenation, less substituted alkenes will complex __ readily to the surface of the metal catalyst, resulting in a __ rxn rate.
more; fast
Although NH and OH peaks occur in the same range of the IR spectrum, amines can readily be distinguished from alcohols by their IR spectra bc the NH peak is __________ which the OH peak tends to be ________
narrow and weak / medium; broad & strong
A compound that contains an odd number of _____ atoms gives a molecular ion an odd mass.
nitrogen
The _____ rule reflects the fact that an odd number if nitrogen atoms in a compound causing the compound to have an ______ molecular mass
nitrogen / odd
LiAlH4 provides a source of the H- ion, wh acts as a strong __. The rxn of the LiAlH4 w an alkyl halide or epoxide therefore proceeds by an __ mech.
nucleophile; Sn2
an odd number of N atoms = an even number of N atoms =
odd molecular mass even molecular mass
The presence of N atoms in a compound can sometimes be inferred from the molecular mass: for an odd molecular mass:
odd number of N atoms
When an epoxide reacts with OH- to form a 1,2-diol, nucleophilic attack must occur from the _______ face to/as the epoxide ring, resulting in overall _______ addition of the two OH groups
opposite / anti
Antabuse, a drug given to alcoholics, acts by interfering w the __ of acetaldehyde to the acetate anion.
oxidation
Is this rxn shown an ex of oxidation or reduction? butanol -> carboxylic acid w 2 C chain
oxidation
An organic rxn where C-O bonds replace C-H bonds is classified as ________ since O is a _______ electronegative element than C.
oxidation / more
match each process to the correct description. Assume "Z" reps an element more EN than C.
oxidation results in... an increase in the # of CZ bonds reduction results in... an decrease in the # of CZ bonds an increase on the # of C-H bonds... reps reduction a decrease in the # of C-H bonds... reps oxidation
An organic rxn where C-O bonds replace C-H bonds is classified as __, since O is a __ electronegative element than C
oxidation; more
______ cleavage of an alkene breaks both the sigma and pi bonds of the double bond to form two carbonyl groups.
oxidative
NAD+ is used to ______ an alcohols to a(n) ______ in biological systems.
oxidize; carbonyl
A common method used for oxidative cleavage of alkenes uses ________ as the oxidant in the first step; this method is called ________.
ozone / ozonolysis
A common method used for oxidative cleavage of alkenes uses ______ (O3) as the oxidant in the first step; this method is called _______.
ozone, ozonolysis
A common method used for oxidative cleavage of alkenes uses __ (O3) as the oxidant in the 1st step; this method is called__
ozone; ozonolysis
Rxn of an alkene with O3 produces an unstable ______ intermediate, wich must then be _____ to give aldehydes and/or ketones as products.
ozonide / reduced
Rxn of an alkene w O3 produces an unstable __ intermediate, wh must then be __ to give aldehydes and/or ketones as products.
ozonide; reduced
What is a typical reagent used to form an epoxide ......
peroxyacid
The typical reagent type used to form an epoxide from an alkene is an __ such as mCPBA.
peroxyacid or peracid
The typical reagent type used to form an epoxide from an alkene is a(n)______ such as mCPBA.(Give the reagent type, not the specific name for mCPBA).
peroxyacid, peracid, or peroxy acid
Particles of electromagnetic radiation are called _______ and each has a discrete amount of energy called a _______
photons / quantum
Hydrogenation allows us to determine how many degrees of saturation are due to __
pi bonds and rings
Certain compounds containing ______ C-X sigma bonds may be reduced with reagents such as LiAlH4 in a nucleophilic ________ rxn.
polar / substitution
Certain compounds containing ______ C-X σ bonds may be reduced with reagents such as LiAlH4 in a nucleophilic ______ reaction.
polar, substitution
Certain comps containing __ C-X sigma bonds may be reduced w reagents such as LiAlH4 in a nucleophilic __ rxn
polar; substitution
aldehyde
primary alcohol
Alcohol oxidations are accompanied by a characteristic color change as the ______ Cr(VI) is reduced to Cr3+, which is ______ in solution.
red-orange / green
Alcohol oxidations are accompanied by a characteristic color change as the __ Cr(6+) is reduced to Cr(3+), wh is __ in sol.
red-orange; green
Identify the reaction type that occurs when an alkyne is converted to an alkene or an alkane.
reduction
Identify the rxn type that occurs when an alkyne is converted to an alkene or an alkane.
reduction
The symbol [H] is commonly used to indicate a(n) _______ rxn.
reduction
The symbol [H] is commonly used to indicate an __ rxn
reduction
______ of an alkene forms an alkane by addition of H2
reduction
Reaction of an alkene with H2 to form an alkane is an example of a(n)_______ rxn because there is a(n)________ in the number of C-H bonds.
reduction / increase
Reaction of an alkene with H2 to form an alkane is an example of a(n) _____ reaction because there is a(n) _____ in the number of C-H bonds.
reduction, increase
_______ rxns form predominately or exculsivley one constitutional isomer
regioselective
Epoxidation results in syn addition to an alkene. The stereochemistry of the alkene is therefore ______ in the final product.
retained
Epoxidation results in syn addition to an alkene. The stereochemistry of the alkene is therefore _____ in the final product.
retained ***syn addition will result in the alkene stereochemistry being retained in the epoxide. groups that were cis remain cis.
Epoxidation results in syn addition to an alkene. the stereochemistry of the alkene is therefore __ in the final product.
retained; cis -> cis, trans -> trans
In gas chromatography, the amount of time a particular compound takes to exit the column is called its _______ time. The higher the BP of the substance, the _______ the time it will take to exit the column.
retention / longer
During catalytic hydrogenation, the alkene complexes to the metal catalyst and two H atoms are transferred to the ______ face(s) of the pi bond, resulting in ______ addition.
same / syn
An epoxide is formed via a single step process, in wh bonds are broken and formed simultaneously. the 2 new sigma bonds bw c & o must therefore form on the __ sides of the double bond, resulting in __ addition
same, syn
During catalytic hydrogenation, the alkene complexes to the metal catalyst and 2 H atoms are transferred to the __ face(s) of the pi bond, resulting in __ addition.
same; syn
ketone
secondary alcohol
Rank the following alkyl halides in order of rate of rxn w LiAlH4. (least -> greatest) -methyl, primary, secondary
secondary, primary, methyl
Match each structure to the expected set of mass spectral data, based on the major fragmentation pathway for each compound
see mass spectrometry file saved
amine (N-RRR)
sharp medium intensity peak(s) 3400-3200cm^-1
amide (N=ORRR)
sharp medium intensity peak(s) 3400-3200cm^-1 as well as strong peak at 1660cm^-1
The rxn that allows enantioselective synthesis of epoxides is called the __ epoxidation.
sharpless
Epoxidation is 1 ex of a concerted process. during the formation of an epoxide, bond formation occurs __ bond breakage.
simultaneous w/
Absorptions in the 4000-2500cm^-1 range of the IR spectrum are typical of _____ bonds to hydrogen, whereas absorptions in the 2000-1500cm^-1 range are typical of _____ bonds.
single / double
When hydrogenation of two alkenes produce the same alkane, the more stable alkene has the _______ heat of hydrogenation
smaller
Heat of hydrogenation can be used as a measure of _______ when looking at two different alkenes that can be hydrogenated to _______ alkane(s).
stability; the same
Molecules, like all other matter, have a specific energy _________ of different types. For a molecule to absorb radiation, the energy of the radiation must match the energy _______ btwn the two energy _______ in the molecule.
states / difference / states
Epoxidation of an alkene is a __ rxn bc cis and trans alkenes yield __ stereoisomers as products.
stereo specific; diff
A rxn such as epoxidation, in which rxn of a specific stereoisomer leads to a specific stereochemical outcome, is correctly described as_______
stereospecific
The specific frequency of IR radiation absorbed by a particular bond depends on the ______ of the bond and the ______ of the bonded atoms.
strength / masses
ketone C=O group
strong peak around 1700 cm^-1
Catalytic hydrogenation of an alkene double bond results in the addition of 2 H atoms to the same face of the double bond. This is called _____ addition.
syn
Which term correctly describes the stereochemistry of the addition of H2 across a double bond in catalytic hydrogenation?
syn
____ dihydroxylation results when an alkene is treated KMnO4 or OsO4, where each reagent adds two oxygen atoms to the same side of the double bond
syn
The formation of an epoxide results in _______ addition to the alkene meaning that the two C-O bonds of the 3-membered ring will always be on (the ) _____ side of the compound.
syn / same
Reaction of an alkyne with H2 in the presence of a lindlar catalyst will result in _____ addition of H2 across the double bond, producing a ______ alkene.
syn /cis
Catalytic hydrogenation of an alkene double bond results in the addition of 2 H atoms to the same face of the double bond. this is called __ addition
syn addition
Rxn of an alkyne w/ H2 in the presence of a Lindlar catalyst will result in __ addition of H2 across the double bond, producing a __ alkene
syn, cis
During catalytic hydrogenation, the addition of H2 results in __ addition bc the alkene complexes to the surface of the metal catalyst and hydrogen atoms are added to the __ face of the alkene.
syn; same
How would you rank alkenes in order of INCREASING heat of hydration?
tertiary (most stable ) > secondary > primary (least stable)
In what way does the sharpless reagent control the stereochemical outcome of the sharpless epoxidation?
the DET isomer blocks one face of the alkene, and the stereochemistry of the DET determines which face is blocked
When a molecule interacts with IR radiation...
the bonds of the molecule vibrate in various ways
Wavelength =
the distance btwn one point on a wave to the same point on the adjacent wave (lambda)
2 isometric alkene will yield __ products in a hydrogenation rxn; therefore any diff in the heat of hydrogenation for the 2 hydrogenation rxns must be due to a diff in the relative stabilities of the 2 alkene.
the same
Two isomeric alkenes will yield ______ products in a hydrogenation rxn; therefore any difference in the deltaH for the two rxns must be due to a difference in the relative stabilities of the two alkenes.
the same ***isomeric alkenes will produce the same alkane when hydrogenated
Which of the following correctly defines green chemistry?
the use of environmentally benign methods for synthesis
What condition must be fulfilled for a bond to absorb IR radiation?
there must be a change in dipole moment during the vibration
Wh of the following options correctly describe all reducing agents in organic chem?
they provide the equiv of 2 H atoms to the rxn
Cis- and trans-2-butene can both by hydrogenated to butane; thus their energies can be compared. The __ -isomer releases less energy upon hydrogenation therefore __ -2-butene higher in energy.
trans; cis
The halogens Br and Cl each have two naturally occurring isotopes of high abundance. The mass spectrum of a compound containing one Br or one Cl atom will show TWO molecular ion peaks that are ________ mass units apart, at M and M+ _______.
two / two
A 13C NMR spectrum gives information about the _____ of different kinds of carbon atoms and _____ _____ of carbon atoms in an organic compound
type; chemical environment
For a bond to absorb in the IR, there must be a change in the dipole moment during the _________
vibration
Absorption of IR radiation causes changes in the _____ modes of a molecule, causing its _____ to bend, stretch, and twist. This behavior is characteristic of the type of _____ groups present in the molecule
vibrational; bonds; functional
The ____________ is inversely proportional to the wavelength and reported in reciprocal centimeters (cm−1).
wavenumber
Instead of wavelength or frequency, IR spectroscopy uses _____ to record the absorption of IR radiation. This quantity is reciprocal of _____ and is _____ proportional to energy
wavenumbers; wavelength; directly
The lower the % s-character of a bond, the _______ the bond and therefore the _______ the wavenumber for its IR absorption.
weaker / lower
What is the correct order of the types of electromagnetic radiation in order of increasing wavelength? (shortest to longest wavelength)
x-ray < UV radiation < visible light < IR radiation < radio waves
Hydrogenation allows us to determine how many degrees of unsaturation are due to _______.
π-bonds