Organic Chemistry (Kaplan MCAT 2019)
nucleophilicity _______ with increasing electron density because ______
increases more negative charge
what is the least reactive carb acid derivative? most reactive?
least- amides most-anhydride
bulkier molecules are _____ nucleophilic
less
a compound that rotates plane polarized light to the left is called what?
levorotatory, -
electrophiles will almost always act as ______ ______ in reactions
lewis acids
axial vs equatorial
substituents attached perpenticular (straight up and down) are axial and those pointing outwards parallel are equatorial
structural isomers share only a _____ _______ and have _______ physical and chemical properties
molecular formula differing
When two atomic orbitals combine they form
molecular orbitals
non bonded strain (van der Waals repulsion) occurs when
nonadjacent atoms or groups compete for the same space
TLC mobile phase
nonpolar solvent, which climbs the carb through capillary action
____ and _____ amino acids tend to by hydrophobic and reside in the interior of proteins
nonpolar-nonromantic and aromatic
Gas Chromatography mobile phase
nonreactive gas
mess compounds are made up of two halves that are mirror images, thus they are _____ optically active
not
in TLC, the polar phase is nonpolar, so polar compounds will ________, and nonpolar samples will _________.
not move very far move pretty far
how can you synthesize a carboxylic acid?
oxidation of primary alcohols or aldehydes usually using Na2Cr2O7, K2Cr2O7, CrO3, or KMnO4
almost all organic reactions can be divided into two groups...
oxidation-reduction and electrophile-nucleophile
O2, CrO4-, and Cl2 are examples of good _______ agents
oxidizing
if an aldehyde is not the highest priority group, how will it be named?
oxo-
if a ketone isn't the highest priority group, how is it named?
oxo- or keto-
what are the 4 main reactants in the gabriel's synthesis?
potassium pthalimide diethyl bromomalonate alkyl halide water
B lactam have very high _____ strain because....
ring strain they are a 4 membered rings with both torsional and angle strain
aldehyde naming
replace -e with -al
carboxylic acid naming
replace -e with -oic acid
amide naming
replace -oic acid with -amide
lactam naming
replace -oic acid with -lactam
anhydride naming
replace the acid at the end of the name of the parent carboxylic acid with anhydride
at the end of filtration one is left with the solid, called the ________, and the liquid, called the _______
residue filtrate
what stabilizes the negative charge on a deprotonated carboxylic acid
resonance and Electron withdrawing oxygens
resonance of amides
resonance between the carbonyl and the lone pair on the nitrogen stabilizes the bond and restricts its motion
rotation is limited around the peptide bond becasue
resonance gives the C-N bond partial double bond character
covalent bonding
results from the sharing of electron pairs between two atoms
cleavage of anhydride using alcohols
results in the formation of an ester and carboxylic acid
why are ketones less likely to react with nucleophiles than aldehydes
the extra alkyl group destabilizes the carbanion and increases steric hinderance
gravity filtration is used when
the product of interest is in the filtrate
vacuum filtration is used when
the product of interest is in the solid
optical activity refers to
the rotation of plane polarized light by a chiral molcule
amides may or may not participate in hydrogen bonding so their boiling points are either _____________ or __________ than that of carboxylic acids
the same lower
aldehyde naming
usually are number 1 replace -e of the parent alkane with -al
why would esterification reactions not be carried out in water?
water molecules would hydrolyze the desired products back into the parent carboxylic acids
alcohols are poor leaving groups but they can by protonated or reacted to form goof leaving groups such as...
water, mesylates, or tosylates
strength of pi and sigma bonds
sigma bonds are stronger, so if a bond is broken it is usually a pi bond
methanoic acid common name
formic acid
what are the common names for: methanoic acid ethanoic acid propanoic acid
formic acid acetic acid propionic acid
a proton with 3 adjacent hydrogens will have how many peaks? what will the area ratios be?
4 1:2:2:1
the normal region of IR spectra are from
400-4000 cm-1
gamma-butyrolactone contains a ______ membered ring
5
cyclic carboxylic acid synthesis results in ______ and _______ membered rings and is driven forward by _________
5 and 6 membered rings ring stability and heat
how much s character does an sp bond have? sp2? sp3?
50 33 25
aromatic hydrogens appear in the ________ ppm range
6-8.5
quinones
-phenols treated with oxidizing agents -Named by indicating the position of the carbonyls numerically & adding quinone to the name of parent phenol -Serve as electron acceptors in e- transport chain
chemoselectivity
-preferential reaction of one functional group in the presence of other functional groups
What is the most common form of NMR
-proton NMR, which uses the 1H nucleus
protons on sp3 hybridized carbons are usually in the ________ ppm range protons on sp2 hybridized carbons are usually in the ________ ppm range protons on sp hybridized carbons are usually in the ________ ppm range
0-3 4.6-6 2-3
what is the Rf if the solvent traveled 10 cm and the compound traveled 5 cm
0.5
when looking at plane polarized light rotation, chemists use what standard conditions?
1 g/ml concentration 1 dm (10 cm) tube length
n possible values? l possible values? m(l) possible values? m(s) possible values?
1 to infinity 0 to (n-1) -l to l -1/2 or +1/2
If 1000 triacylglycerols undergo saponification, what will be the product?
3000 soap molecules and 1000 glycerols
most oxidizing agents will turn aldehydes into __________, PCC on the other hand will not because ________
carboxylic acids it is not strong enough to oxidize past the point of aldehyde
functional groups from more to less reactive
carboxylic acids and their derivatives, aldehydes, ketones, alcohols and amines
boiling points of carboxylic acids
carboxylic acids can form more than one hydrogen bond, so there is an even increased boiling point compared to alcohols also, increased molecular weights increase boiling point
esters are formed by the condensation reaction of
carboxylic acids or anhydrides with alcohols
aldehydes are ______ _______, meaning they appear at the end of a parent chain
chain terminating
the most stable conformation of cyclohexane is the ______ conformation, which minimizes all three types of strain
chair
cyclohexane exists mainly in what configurations?
chair, boat, or stint/skew-boat
aldehydic hydrogens appear in the ________ ppm range
9-10
nucleophilicity is determined by four major factors
charge, electronegativity, steric hinderance, solvent
tosylates
contain the functional group -SO3C6H4CH3, which is derived from toluenesulfonic acid
Retardation Factor (Rf)
A ratio used in thin-layer chromatography to identify a compound; calculated as how far the compound traveled relative to how far the solvent front traveled.
Arrhenius acid
Produces H+ ions when dissolved in water
Arrhenius base
Produces OH- ions when dissolved in water
characteristics of the conversion from a hemiacetal to an acetal
SN1, the -OH is lost as a molecule of water, forming a carbocation, the alcohol then attacks the carbocation
does backside attack occur in SN1 or SN2?
SN2
salts of carboxylic acid naming
begin with the cation, followed by the name of the acid with the ending -oate replacing -oic acid
saponification
The process of soap formation
The alkene is named ____ if the two highest-priority substituents on each carbon are on the same side of the double bond
Z zame zide
plane polarization rotatio reactions measured at different concentrations and tube lengths than the standard conditions can be convereted to a standardized specific rotation using this equation
[a]= a(obs)/(c x l) specific rotation in degrees= observed rotation in degrees divided by concentration (g/ml) times path length (dm)
carbonyl group
a chemical group consisting of a carbon atom linked by a double bond to an oxygen atom two examples are ketones and aldehydes
gauche conformation
a conformation with a 60 degree dihedral angle between the largest groups
coordinate covalent bonds
a covalent bond in which one atom contributes both bonding electrons
alkanes
a hydrocarbon containing only single covalent bonds
zwitterion
a molecule or ion having separate positively and negatively charged groups, such as an amino acid
when an aldehyde is mixed with a diol it forms an _______. when a ketone is mixed with a diol it forms a _______.
acetal ketal
ethanoic acid
acetic acid
ethanoic acid common name
acetic acid
functional groups that act as acids include
alcohols, aldehydes and ketones at the alpha carbons, carboxylic acids, and most carboxylic acid derivatives
what are the four reactant in strecker synthesis?
aldehyde NaH4Cl KCN H2O
aldol condensation basics
aldehyde or ketone acts as an electrophile (keto form) and a nucleophil (enolate form), the product is the formation of a carbon-carbon bond an enolate is formed, which attacks the cabonyl carbon, forming an aldol, then -OH is removed as water, forming a double bond
strecker synthesis reactant
aldehyde, ammonium chloride (NH4Cl), and potassium cyanide (KCN)
are aldehydes or alcohols higher priority groups when naming?
aldehydes
acidity of the alpha hydrogens on ketones compared to aldehydes
aldehydes are more acidic because the ketone has more EDGs
what is more reactive, ketones or aldehydes?
aldehydes because less sterics
NMR spectroscopy measures
alignment of nuclear spin with an applied magnetic field, which depeds on the magnetic environment of the nucleus itself.
sp2 hybridization are seen commonly in what?
alkenes
acyl derivatives examples?
all molecules with a carboxylic acid derived carbonyl carboxylic acids, amides, esters, anhydrides, and others
during NMR spec, nuclei may be in the ____ state or in the ____ state the ____ state is higher energy the _____ state is lower energy
alpha or beta state higher energy-Beta lower energy-alpha
during NMR spec, tadiofrequency pulses push the nucleus from the ___ to the ___ state, and these ______ can be measured
alpha to beta state frequencies
the carbon adjacent to the carbonyl is termed the _____ carbon, the carbon to away is termed the ______ carbon and so on
alpha, beta, gamma, delta
conjugation requires
alternating single and multiple bonds because this pattern aligns a number of unhybridized p orbitals down te backbond of the molecules
carboxylic acid derivate examples
amides esters and anhydrides
why do amides contain partial double bond character between the nitrogen atom and carbonyl carbon?
amides have two resonance structures so the true structure is a hybrid of the two
____ and _____ are the main functional groups that act as bases
amines and amides
amino acids contain
amino group, carboxyl group, R group, hydrogen
carboxylic acids can be converted to amides if the incoming nucleophile is ______ or a ______
ammonia (NH3) amine
cleavage of anhydride using ammonia
ammonia acts as a nucleophile and cleaves the anhydride bond results in a carboxylic acid and an amide
amino acids are amphoteric because they have both.....
an acidic carboxyl group and basic amino group
anhydrides can be cleaved by the addition of a nucleophile addition of ammonia or an amine results in ________ addition of alcohol results in ________ addition of water results in ________
an amide and a carboxylic acid ester and a carboxylic acid two carboxylic acids
Ring strain arises from three factors
angle strain, torsional strain, or non bonded strain (sterics)
symmetric anhydrides are named by replacing acid with
anhydride
carboxylic acid derivatives ranked by electrophilicity
anhydrides are the most reactive, followed by carboxylic acids and esters, then amides
Reactivity of carboxylic acid derivatives from most to least reactive
anhydrides, esters and carboxylic acids, amides
the most stable Newman projection for butane
anti
what is the conformation called when the two highest priority groups are 180 degrees apart?
anti
two times of staggered conformation
anti and gauche
If the signs of the wave functions are different, a higher-energy _____ orbital is produced
antibonding
alpha-racemization
any aldehyde or ketone with a chiral alpha carbon will rapidly become a racemic mixture as the keto and enol forms interconvert
alpha carbon
any carbon attached directly to a carbonyl carbon
primary alcohols are oxidized to carboxylic acids by
any oxidizing agent besides PCC
the polar layer during extraction is the ______ phase and the nonpolar layer is the _______ phase
aqueous organic
Deprotection of alcohols is done by
aqueous acid
what will convert a cyclic acetal to a carbonyl and a dialcohol
aqueous acid
to push a retro-aldol reaction ______ and ______ are adde
aqueous base heat
positively charged (basic) amino acids
arginine lysine histidine all side chains has positively charged nitrogen atoms
Chapter 4
Chapter 4
Chapter 5
Chapter 5
Chapter 6
Chapter 6
Chapter 8
Chapter 8
Chapter 9
Chapter 9
the form of phosphoric acid in strongly basic conditions
PO4
when two equivalents of alcohol are added to an aldehyde, what is the product
acetal
what is the most oxidized functional group that appears on the MCAT?
carboxylic acids
mesylates
contain functional group -SO3CH3, which is derived from methanesulfonic acid
kinetic is to thermodynamic as ______ is to _____
speed stability
a scientist takes a 0.5 g/ml solution of an unknown pure dextrorotary organic molecule and places it in a test tube with a diameter of 1 cm. he observed that a plane of polarized light rotates 12 degrees. what is the specific rotation of this molecule?
+240 degrees 12/(0.5 g/ml)(0.1 dm)=12/0.05=240 dextrorotary=+
Gabriel Synthesis
- An amino acid is generated from phthalimide (nucleophile) and diethyl bromomalonate, using two SN2 reactions, hydrolysis, and decarboxylation.
proton NMR is good for
- Determine the relative number of protons and their relative chemical environments - Showing how many adjacent protons there are by splitting patterns. - Inferring certain functional groups
Alcohols are named by replacing the suffix -e with _____ or by naming the alkyl group as a derivative followed by _____
-ol (2-propanol) alcohol (ethyl alcohol)
alpha hydrogens
- hydrogens connected to an alpha carbon - are acidic
enolate
- results from deprotonation that is stablized by resonance with the carbonyl - good nucleohpiles
Nonpolar, nonaromatic amino acids
- tend to have side chains that are saturated hydrocarbons alanine valine leucine isoleucine glycine proline methionine
Recrystallization
- the product is dissolved in a minimum amount of hot solvent - if the impurities are more soluble, the crystals will reform while the flask cools, excluding the impurities
acids with a pKa below ______ are considered strong acids
-2
weak organic acids often have pKa values between
-2 and 20
if an aldehyde is attached to a ring, the suffix _____ is used
-carbaldehyde
ketones are named by replacing the -e of the parent alkane with
-one commonly names by listing the alkyl groups in alphabetical order followed by ketone
in a hemiacetal the central carbon is bound to what?
-OH, -OR, -H, -R
nucleophilic substitution reaction
-SN1 and SN2 -nucleophile forms a bond with a carbon and a leaving group leaves
heterolytic reactions
-a bond is broken and both e- are given to one of the 2 products essentially is the opposite of coordinate covalent bonding
dicarboxylic acid naming
-dioic acid
geminal diols
-diols with hydroxyl groups on the same carbon
reducing agents
-elements in redox reactions that donates e- to another species it losses e- so it becomes oxidized
carboxylic acids are names by replacing the -e of the parents alkane with
-oic acid
pKa can be calculated by
-log(Ka)
leaving groups
-molecular fragments that retain e- after heterolysis
nucleophiles
-nucleus loving -negatively charged so they are attracted to the + nucleus -have lone pairs or π bonds that can be used to form covalent bonds to electrophiles
Jones oxidation
-uses CrO3 dissolved with H2SO4 in acetone -oxidizes primary alcohols to carboxylic acids or secondary alcohols to ketones
functional groups ordered from least to most oxidized
1-alkanes 2-alcohols, alkyl halides, amines 3-aldehydes, ketones, imines 4-carboxylic acids, anhydrides, esters, amides 5-carbon dioxide
alcohols are neamed by replacing the e at the end of the alkane with ol, so a terminal alcohol with all single bonds and 6 carbons would be called
1-hexanol
ststrecker synthesis steps
1. ammonia attacks the carbonyl carbon forming an imine 2.an aminonitrile is generated by KCN attacking the imine 3. an amino acid is generated from the aminonitrile
esterification steps
1. carbonyl oxygen is protonated 2. primary alcohol attacks carbonyl carbon 3. -OH on alpha carbon is protonated to H2O and then leaves as a leaving group 4. carbonyl is deprotonated
Steps in Problem Solving
1. know the nomenclature 2. ID the functional groups 3. ID the other reagents 4. ID the most reactive functional groups 5. ID the first step 6. consider stereoselectivity
nucleophilic acyl substitution steps
1. nucleophilic addition 2. elimination of a leaving group (H2O) and formation of the carbonyl
steps of michael addition
1. the base deprotonates the alpha carbon, making it a good nucleophile 2. the carbanion attacks the double bond of an ab-unsaturated carbonyl compound, resulting in michael addition
R and S forms
1. used the Cahn-Ingold Prelog priority rules to assign priority to the four substituents on the chiral center -only look at the atoms that are directly attached to the carbon -higher atomic number gets priority *if tie is there look at the combination of the atoms attached to the atom attached to the chiral center* -double bond, bonded to it twice 2. draw a circle connecting 1 to 2 to 3 clockwise --> R - RIGHT counterclockwise --> S - LEFT 3. If H is not going into the page (dashed lines or up/down) then opposite configuration
an electron is known to be in the n=4 shell and the l=2 subshell. how many possible combinations of quantum numbers could this electron have?
10
carboxylic acid hydrogens appear in the ________ ppm range
10.5-12
each orbital contains ______ electrons
2
two different ways to name an pentene with the double bond between the 2nd and 3rd carbon
2-pentene or pent-2-ene
isopropyl alcohol
2-propanol
What two peaks would you expect to see in the IR spectrum of a carboxylic acid?
3000 O-H 1750 C=o
meso compound
A compound with chirality centers and an internal plane of symmetry causing it to be an achiral molecule
fischer projection
A method of drawing organic molecules in which horizontal lines are coming out of the page (wedges) and vertical lines are going into the page (dashes)
chiral
A molecule or carbon atom bonded to four different groups and without a plane of symmetry; thus, it is not superimposable upon its mirror image and has an enantiomer.
achiral
A molecule that is superimposable on its mirror image
oxidation state
A positive or negative whole number that represents the "charge" an atom in a compound would have if all shared electrons were assigned to the atom with a greater attraction for those electrons.
solute
A substance that is dissolved in a solution.
NMR shifts for Alkyl groups, alkynes, alkenes, aromatics, aldehydes, and carboxylic acids
Alkyl groups 0-3 ppm alkynes 2-3 ppm alkenes 4.6-6 ppm aromatics 6-8.5 ppm aldehydes 9-10 ppm carboxylic acids 10.5-12 ppm
column chromatography stationary phase
Alumina or silica gel
the form of phosphoric acid in strongly acidic conditions
H3PO4
phosphoric acid
H3PO4 extremely important biochemically, forms the high energy bonds of ATP
nitriles
C triple bond N
most reduced form of carbon
CH4, where it has an oxidative charge of -4
most oxidized form of carbon
CO2, where it has an oxidative charge of +4
Chapter 3
Chapter 3
Chapter 1
Chapter 1
Chapter 10
Chapter 10
Chapter 11
Chapter 11
Chapter 2
Chapter 2
ionic bonding
Chemical bonding that results from the electrical attraction between cations and anions, electrons are transferred from one atom to another
Ubiquinone
Coenzyme Q vital electron carrier associates with Complexes 1, 2, and 3 of the ETC
aminonitrile
Compound containing an amino group and a nitrile group
Stereoisomers
Compounds with the same structural backbone, but a different arrangement in space (wedges and dashes)
aldol
Contains both aldehyde and alcohol functional groups.
Jones reactions require what?
CrO3, H2SO4, and acetate
tosylates are prepared using
alcohols with p-tosylsulfonyl chloride, forming esters of tosylsulfonic acid
When a new nucleotide is incorporated into a DNA strand by _______________, the following phosphate(s) of the incoming nucleotide is released:
DNA polymerase pyrophosphate (PPi) (P2O7)
Dextrorotary vs Levorotary
Dex is clockwise, Lev is Counter
the alkene is named _____ if the two highest-priority substituents on each carbon are on the opposite side of the double bond
E
how to remember what examines are?
ENEamines ene=double bond amine=nitrogen
electron withdrawing groups and electron donating groups effect on phenol acidity
EWGs increase acidity and EDGs decrease acidity
diols/glycols
alcohols with two hydroxyl groups
How are peptide bonds broken?
H+ or -OH hydrolysis
byproduct of anhydride synthesis
H2O
what is the leaving group of a nucleophilic acyl substitution?
H2O
which of the following are lewis bases? Ag+ H2O NH3
H2O and NH3
at physiological pH what two phosphoric acids are in the highest concentration
H2PO4 and HPO4
Before absorbing an ultraviolet photon, electron scan be found in: The HOMO only The LUMO only Both the HOMO and LUMO neither the HOMO nor the LUMO
HOMO only
what is the major historical distinction between HPLC and column chromotography?
HPLC at high pressure
what is the major current distinction between HPLC and column chromotography?
HPLC is computerized
phenols
Hydroxyl groups attached to aromatic rings -Two groups on adjacent carbons are called ortho- or o- -Two groups separated by a carbon is called meta- or m- -Two groups on opposite sides of the ring are called para- or p-
How are hydroxyquinones produced?
Hydroxyquinones are produced by the oxidation of quinones adding a variable of additional hydroxyl groups.
In a protic solvent, which halogen would be the best nucleophil
I-
some examples of good leaving groups
I-, Br-, Cl-
phylloquinone
Important for photosynthesis and reactions of clotting factors in blood
Solvent
In a solution, the substance in which the solute dissolves.
all amino acids are ___-isomers, and all have ____ configurations except for cysteine
L-isomers S
amides can be reduced to amines using
LiAlH4
carboxylic acids can be reduced by __________, but not by less reactive __________.
LiAlH4 NaBH4
what is stronger, NaBH4 or LiAlH4, and why?
LiAlH4 is a more powerful reducing agent that NaBH4, because the Al-H bond is weaker and thus less stable than B-H bond
Immiscible liquids
Liquids that repel each other and do not mix to form a solution
_______ is the medical application of NMR spec
MRI
naming of quinones
Numerically indicate carbonyls and add quinone to name of parent phenol
difference between NH and OH peaks in IR spec
OH is broad and NH is sharp
The release of ________ provides energy for the formation of a new phosphodiester bond on a DNA strand
PPi (pyrophosphate) (P2O7)
spin-spin coupling (splitting)
Occurs when we have 2 protons in close proximity to each other that are not magnetically identical
rotary evaporator (rotovap)
Once the desired product is extracted substance is placed in rotovap in order to evaporate the solvent Leaving solute extract behind
primary alcohols can be oxidized to aldehydes by
PCC
to oxidize a primary alcohol to an aldehyde you must use
PCC
primary alcohols can be oxidized by one level to become aldehydes by ______, otherwise they are oxidized all the way to carboxylic acids by _______
PCC CrO3, Na2Cr2O7, K2Cr2O7
secondary alcohols can be oxidized to form ketones by
PCC or any stronger oxidizing agent
condensation reactions
Result in the formation of a bond between two monomers with the release of a water molecule
relative configuration
The Spatial arrangement of groups in a chiral molecule compared to another chiral molecule.
decarboxylation
The complete loss of a carboxyl group as carbon dioxide
the coupling constant, J, is
The magnitude of splitting in NMR spectroscopy, measured in hertz.
retro-aldol reaction
The reverse of an aldol condensation reaction, in which a carbon-carbon bond is cleaved with heat and base, yielding two aldehydes, two ketones, or one of each.
For any molecule with n chiral centers...
There are 2^n possible stereoisomers.
When is fractional distillation used?
To separate two compunds with boiling points less than 25 degrees apart
isomers
Two different molecules that have the same chemical formula but different structures
what is a wash?
When you are using the extraction to remove impurities rather than separate out the desired product.
peaks that have more than 4 shifts will be referred to as
a multiplet
examines contain
a nitrogen and a double bond
LiAlH4 will reduce esters to
a pair of alcohols
amide synthesis is done by the reaction of a carboxylic acid derivative with _______
a primary or secondary amine or ammonia
SN1 reactions yield what product
a racemic mixture
both the strecker and gabriel synthesis result in
a racemic mixture of amino acids
oxidation reduction reactions
a reaction that involves the transfer of electrons between reactants
during ion exchange chromatography, after all other compounds have moved through the column, ____________ is used to elute the charged molecules that have stuck to the column
a salt gradient
what can cause the deprotonation of an alpha carbon, causing an enolate to form
a strong base, such as OH-, LDA, KH
what is the reverse of extraction?
a wash
what is the final product of an aldol condensation?
ab-unsaturated carbonyl
IN an IR spectrum, how does extended conjugation of double bonds affect the absorbance band of carbonyl (C=O) stretches compared with normal absorption? The absorbance band will occur at a lower wavenumber The absorbance band will occur at a higher wavenumber The absorbance band will occur at the same wavenumber The absorbance band will disappear.
absorbance will occur at a lower wavenumber
UV spectroscopy measures
absorption of UV light, which causes movement of electrons between molecular orbitals
oxidizing agents
accepts an electron from another species because it is gaining electrons it is itself reduced
what is the smaller possible ketone?
acetone
When benzaldehyde is reacted with acetone, which will act as the nucleophile? Benzaldehdye, after addition of strong acid Benzaldehyde after reaction with strong base Acetone, after addition of strong acid Acetone, after reaction with strong base
acetone after reactions with a strong base
what can be used to increase solubility during extraction?
acid base properties
the carboxyl group on an amino acid is ________ and the amino group is ______
acidic basic
How to separate a racemic mixture
add another enantiomer, this will create two diastereomers diastereomers have different physical properties and can be separated by common lab techniques such as crystallization, filtration, or distillation
symmetric anhydrides can be split into two carboxylic acids by
adding H2O
moelcular orbitals are obtained mathematically by ......
adding or subtracting the wave functions of the atomic orbitals
how do hydroxyquinones differ from quinones?
addition of one or more hydroxy groups
in order to separate a biological effector from solution, what chromatographic technique would be used
affinity chromatography using antibodies
if a molecule with two double bonds adjacent to each other and an alcohol, which functional group would take precidence in naming?
alcohol
given an alcohol, alkane, and aldehyde with equally long carbon chain, which will have the highest BP
alcohol because of Hydrogen bonding
aldehydes and ketones undergo reduction to form ______ by _____
alcohols hydrides such as NaBH4 or LiAlH4
what property or properties do structural isomers have in common?
atomic weight
would an acid or a base be most effective in extracting benzoic acid from diethyl ether?
base
good nucleophiles tend to be good _____
bases
saponification is the process where fats are hydrolyzed under ______ conditions
basic
ion exchange chromatography
beads are coated with charged substances to bind compounds with opposite charge
size exclusion chromatography
beads have small pores which trap smaller compounds and allow larger compounds to travel through faster
SN2
bimolecular nucleophilic substitution 1 step (concerted) -nucleophile attacks at the same time the leaving group leaves second order, the rate depends on the concentration of substrate and nucleophile
to appear on an IR spec, vibration of a bond must change the
bond dipole moment
if signs of the wave function are the same a ____ is produced
bonding orbital
nonpolar amino acids
both aromatic and nonaromatic hydophobic and tend to be on the interior of proteins Glycine, Alanine, Valine, Leucine, Isoleucine, Phenylalanine, Tryptophan, Methionine, Proline
priority of functional groups on MCAT from highest to lowest
carboxylic acid, anhydride, ester, amide, aldehyde, ketone, alcohol, alkene, alkyne, alkane
in protic solvents, nucleophilicity of halogens (I, Cl, F, Br) decreases in this order
bottom to top I>Br>Cl>F this is because the protons in solution will be attracted to the nucleophile. HF is the conjugate base of a weak acid and HI is the conjugate base of a strong acid. F will be bound to H and will be unable to attack, while I will be less effected by the protons in solution and will be able to easily attack the electrophile
configurational isomers can only change from one to another by
breaking and reforming covalent bonds
OH IR spec peak (not carboxylic acid)
broad peak at 3300 cm-1
what can slow down a chair flip?
bulky groups are attached (such as a test butyl group)
how are carboxylic acid derivates all formed?
by replacing the -OH on the carboxyl group with another leaving group (-NH2, -OR, and -OCOR)
amphoteric
can act as an acid or a base example: water
protecting groups
can be used to increase steric hindrance or otherwise decrease the reactivity of a particular portion of a molecule
if one diastereomer rotates light clockwise 10 degrees, the other diastereomer will rotate light in which magnitude/direction?
can't tell diastereomers have no relation to each other in terms of optical activity
NaBH4 cannot reduce ________
carboxylic acids
cis-trans isomers (geometric isomers)
carbons have covalent bonds to the same atoms, but these atoms differ in their spatial arrangements due to the inflexibility of double bonds
what is the most common electrophile seen on test day?
carbonyl carbon
hydration of a carbonyl steps
carbonyl is hydrated by water, then protonated, resulting in a geminal diol
why are alcohol boiling points greater than carbonyl boiling points?
carbonyls have no Hydrogen bonding
the primary product of a primary alcohol with a strong oxidant like dichromate will be
carboxylic acid
what is the product of amide hydrolysis?
carboxylic acid and ammonia
NMR spectra are standardized using __________ which is measured in parts per million
chemical shift
whenever you see a carbon with 4 different substituents, this about
chirality
if both groups on a ring are on the same size it is said to be ______ and if they are on opposite sides it is said to be ______
cis trans
R form if 1,2,3 goes ______, S form if 1,2,3 goes _____
clockwise counterclockwise
the system of labeling optical activity always uses + or d- to refer to _______ rotation and always uses - or l- to refer to ______ rotation
clockwise counterclockwise
mnemonic for an R chiral center
clockwise turning of the steering wheel turns the car to the right so it is R
the smaller the number of n the .....
closer the shell is to the nucleus and the lower its energy is
Gas Chromatography stationary phase
coil of crushed metal or a polymer
carboxylic acid derivative synthesis is an example of a _______ reaction that gives off _____
condensation H2O
imine formation is an example of a ________ reaction and also a _______ _________
condensation nucleophilic substitution
esterification is a ______ reaction with ______ as the byproduct
condensation water
anhydrides can be formed how?
condensation of two carboxylic acids
stereospecific reaction
configuration of the reactant determines the configuration of the products
the most similar of all isomers
conformational isomers
conformational vs configurational bonds
conformational= differ in rotation around a single bond configurational= can be interconverted only by breaking bonds
The more stable the ______ _______ is the more likely thatthe proton will leave, making the molecule more acidic
conjugate base
what chemical properties of ubiquinone allow it to carry out its biological functions
conjugated rings that stabilize the ring when accepting electrons, long alkyl tails that allow it to dissolve in the lipid bilayer
enones are a classic example of
conjugation
organic chemistry is deeply rooted in ______ bonding
covalent
HCN reactions with aldehydes and ketones form
cyanohydrins
many anhydrides are ______ because of an intramolecular dehydration of a _______
cyclic dicarboxylic acid
lactones are
cyclic esters
torsional strain results when
cyclic molecules must assume a conformation that has eclipsed or gauche interactions
all optically active amino acids are L/S, except
cysteine
phosphate bonds are high energy because
large negative charges in adjacent phosphate groups and resonance stabilization of phosphates
generally bond strength ____ down the periodic table and therefore acidity _____
decreases increases
nucleophilicity _____ as electronegativity increases because _____
decreases these atoms are more likely to share electron density
in basic solution, an amino acid can become fully _______ and in an acid solution, it can become fully _______
deprotonated- because the bases will take hydrogens protonated- because the acids will donate hydrogens
absolute configuration
describes the exact spatial arrangement of groups of atoms independent of other molecules.
Deshielding mneumonic
deshield, downfield
NMR: deshielding
deshielding of protons occurs when EWGs pull electron density away from the nucleus, allowing it to be more easily affected by the magnetic field
when looking at a fischer projection and the lowest group is on a vertical line (out of the page) you need to
determine the R/S order by numbering 1,2, and 3 and then the true R/S will be the opposite
a compound that rotates plane polarized light to the right is called what?
dextrorotary, +
cis-trans isomers are a subgroup of
diastereomers
are carboxylic acids more or less acidic than dicarboxylic acids?
dicarboxylic acids are more acidic than carboxylic acids because the carboxylic acids act as EWGs towards each other
what serves as the electrophile during gabriel synthesis
diethyl bromobalonate
diasteromers physical and chemical properties
different physical and chemical properties, though come chemical properties may be similar because they have the same functional groups diastereomers have no relation to each other in terms of plane-polarized light
carboxylic acids tend to form ________, pairs of molecules that are connected by two hydrogen bonds
dimers
_____ are often used as protecting groups for aldehyde or ketone carbonyls
diols
strong acids........
dissociate completely
in aqueous solution, PPi will likely
dissociate into 2 inorganic phosphates
during distillation, the liquid with the lowest bp vaporizes first and is collected as the
distillate
More basic molecules have ______ pKa
larger
UV spec is most useful for studying compounds containing
double bonds or heteroatom with lone pairs that create conjugated systems
an imine contains a nitrogen atom
double bound to a carbon atom
splitting patterns include
doublets triplets multiplets
in polar protic solvents, nucleophilicity increase _____ the periodic table
down
pKa decreases _____ the periodic table and increases with ______ electronegativity
down increased
Deshielding moves a peak further ______
downfield
NMR spec with higher chemical shifts are located ______ which is to the _______. Lower chemical shifts are located _____ which is to the _______.
downfield to the left upfield to the right
ketone naming
drop -e add -one
p orbital shape
dumbbell shaped, contain a node where the probability of finding the electron is zrritlsao
what is the conformation called when the two highest priority groups are 120 degrees apart?
eclipsed
spin quantum number (m sub s)
either +1/2 or -1/2, indicating the spin orientation of an electron
2 ways that you can prevent multiple products from forming during aldol condensation?
either use only one type of aldehyde or ketone OR if one molecule has no a-hydrogens then it cannot become an enolate and cannot act as a nucleophile
Electrophiles are
electron loving with a positive charge or positively polarized atom
lewis acid
electron pair acceptor, electrophiles usually
lewis base
electron pair donor, nucleophiles usually
substituents effect on anion stability and acidity
electron withdrawing groups stabilize the anions and make stronger acids, the closer the substituent groups are to the carboxyl group the greater the effect will be
carbonyl carbon is
electrophilic
Imines naturally tautomerize to form:
enamines
just as enols are tautomers of carbonyls, ______ are tautomers of imines
enamines
these stereoisomers are non-superimposable and have opposite configurations at every chiral center
enantiomers
the two categories of configurational isomers
enantiomers and diastereomers
physical and chemical properties of two enantiomers
enantiomers have nearly identical physical and chemical properties, but they rotate light in opposite directions and react differently in chiral environments
alkene and alkyne endings
ene, yne
the conversion between keto and enol is called what?
enolization or tautomerization
during size exclusion chromatography the ________ compounds will travel quicker
larger
cyclopentane exists mainly in what configuration?
envelope
large molecules in the chair conformation are more favorable in the axial or equatorial position?
equatorial
base strength is relative to _______ and is therefore a ________ property
equilibrium position of a reaction thermodynamic
triacyglycerols are what?
esters of long chain carboxylic acids (fatty acids) and glycerol (1,2,3-propanetriol)
carboxylic acids include
esters, amides, and anhydrides
acetaldehyde and acetic acid both refer to molecules with ______ as the parent alkane
ethane
ethyl alcohol
ethanol
what are the products of the transesterification reaction between isopropyl butanoate and ethanol?
ethyl butanoate and 2-propanol
extraction is carried out in a separator funnel, one phase collected and the solvent is then ________
evaporated
imines can undergo tautomerization to form
examines
when is the kinetic product favored?
favored reactions that are rapid, irreversible, at lower temperatures, with a strong, sterically hindered base
SN1 reactions are ______ order and the rate depends on what?
first only the concentration of the substrate
naming esters
first term is alkyl name of the esterifying group second term is the name of parent acid, with -oate replacing -oic acid the group the replaces the H of the alcohol in the carboxylic acid is names as a substituent
alkyl halides are indicates by a prefix:
fluoro, chloro, bromo, iodo
menaquinone
form of vitamin K produced by bacteria in the large intestine
the common names of aldehydes and carboxylic acids that contain only one Carbon is what?
form-
the same common name prefixes are used from both aldehydes and carboxylic acids; _________ for one carbon, _________ for two carbons, ________ for three carbons
form- acet- propion-
what are the common names for: Methanal Ethanal Propanal
formaldehyde acetaldehyde proprionaldehyde
rate determining step for SN1
formation of the carbocation
saponification occurs by
mixing fatty acids with lye (NaOH or KOH)
d orbital shape
four of the d orbitals are closer shaped and the fifth looks like a donut wwrapped around the center of a p orbital
if you were given solution with a BP of 308 K and a solution with BP of 313K, what distillation technique would work best?
fractional, these are close BPs
during affinity chromatography, after the protein is retained in the column, it can be eluted by washing the column with a __________ that does what?
free receptor (or target or antibody) that competes with the bead-bound receptor and ultimately frees up the protein
wavenumber is directly proportional to ______
frequency
NMR spectra are usually plotted as
frequency vs.
reduction
gain of electrons, decrease in oxidation number
what is the conformation called when the two highest priority groups are 60 degrees apart?
gauche
in the presence of water, aldehydes and ketones react to form
geminal diols
Geminal diols vs. Vicinal diols
geminal diols have hydroxyl groups on the same Carbon and vicinal diols have hydroxyl groups on adjacent carbons
________ diols have hydroxyl groups on the same Carbon and _______ diols have hydroxyl groups on adjacent carbons
geminal, vicinal Mneumonic- gemini twins are paired, vicinal are in the vicinity of eachother
what is the dominant strain during flagpole interactions
non bonded strain
all amino acids except _______ are optically active
glycine
diols are also called ?
glycols
weak bases are ____ leaving groups
good
molecules with more than one hydroxyl group show _______ degrees of Boiling Points and Melting Point increases
greater this is due to increased Hydrogen bonding
during a chair flip, the cyclohexane molecule briefly passes through a fourth conformation called what?
half chair
conformational isomers are the same molecule but are ________________.
in different points in their natural rotation
good oxidizing agents
have a high affinity for electrons or have a very high oxidation state. Examples O2, O3, Cl2, MnO4-, CrO4-, CrO2-7. and pyridinium chlorochromate. These contain a metal and a large number of oxygen atoms.
when an amino acid is placed in solution it will do what?
have a positive charge on the amino group and negative on the carboxyl group, making it a zwitterion
to appear on a UV spectrum, a molecule must
have a small enough energy difference between its HOMO and LUMO to permit an electron to move from one orbital to another
good reducing agents
have low electronegativities and ionization energies or contain a hydride ion (H-) Examples- Sodium, Magnesium, Aluminum, Zinc, NaH, CaH2, LiAlH4, NaBH4. These compounds contain a metal and a large number of hydrides.
sigma bonds are formed by ______ or _____ overlap of atomic orbitals
head to head tail to tail
B-dicarboxylic acids may spontaneously decarboxylate when _________
heated
certain cyclic anhydrides can be formed by simply __________
heating carboxylic acids
when one equivalent of alcohol is added to an aldehyde, what is the product?
hemiacetal
when one equivalent of alcohol is added to an ketone, what is the product?
hemiketal
Strong acids have ___ Ka values and _______ pKa values
high low
the more electronegative the atom, the _______ the acidity
higher
carbonyl BP and MPs are ______ than alkanes and _______ than alcohols
higher less
anhydride boiling points compared to carboxylic acids
higher based on much greater weight
boiling points of alcohols compared to analogous hydrocarbons
higher due to intermolecular hydrogen bonding
conjugation shifts the UV absorption spectrum to
higher maximum wavelengths (lower frequencies)
when is the thermodynamic product favored?
higher temperatures, slow reversible reactions, and with weaker and smaller bases
eclipsed conformation
highest energy no separation. or 120 separation.
hydrolysis of amide occurs under what conditions? why?
highly acidic or basic acidic- allow the carbonyl oxygen to become protonated, making the molecule more susceptible to nucleophilic attack by a water molecule
protic solvents can ____ nucleophilicity by _____
hinder protonating the nucleophile or through hydrogen bonding
what is used to maintain solubility during gravity filtration?
hot solvent
Gas Chromatography separates vaporizable compounds based on
how well they adhere to the absorbent in the column
reduction reactions often feature an increase in the number of bonds to ______ and reducing agents often contain ____ bonded to a large number of ______
hydrogen metals hydride ions
carboxylic acids have higher boiling points than their corresponding alcohols primarily because
hydrogen bonding is much stronger than in alcohols
Three intermolecular forces that affect solubility
hydrogen bonding, dipole-dipole interactions, van der waals forces
at physiological pH, inorganic phosphate includes molecules of both
hydrogen phosphate (HPO4) and dihydrogen phosphate (H2PO4)
pyrophosphate is unstable and is
hydrolyzed into two inorganic phosphates
when the alcohol is not the highest priority group it is named as a substituent with the prefix
hydroxy-
what is more acidic in a B-dicarboxylic acid, the alpha hydrogen or the hydroxyl hydrogen
hydroxyl hydrogen
common ammonia derivatives that react with aldehydes and ketones
hydroxylamine (which forms oximes), hydrazine (which forms hydrazones), and semicarbazide (forms semicarbazones)
the IR spec of two enantiomers will be
identical
Thin-Layer And Paper Chromatography is used to
identify a sample
IR spec is best for
identifying the presence of or the absence of functional groups
When is vacuum distillation used?
if boiling points are over 150 degrees C to prevent degradation of the product
when is simple distillation used
if boiling points are under 150 degrees C and are at least 25 degrees C apart
When is HPLC used?
if the sample size is small or if forms such as capillary action will affect the results
the reaction between ammonia and an aldehyde would yield
imine
what is more common, imine form of the examine form?
imine
would acid dissolve better in aqueous acid or aqueous base? why?
in base, like disolves like refers to polarity
esters that are cyclic are called
lactones
the ______ (area under the curve) of an NMR peak is proportional to the number of protons contained under the peak
integration
anytime 2 groups are switched on a chiral carbon, the stereochemistry is
inverted
rotating a Fischer diagram 90 degrees _____ the stereochemistry while rotating it 180 degrees _______ the stereochemistry
inverts retains
switching one pair of substituents in a fischer diagram _____ the stereochemistry of the chiral center. switching two pairs _____ the stereochemistry
inverts retains
gas chromatography/mass spectrometry
ionizes the fragments molecules and passes these fragments through a magnetic field to determine molecular weight or structure
What makes fractional distillation different from simple distillation?
it has more surface area and allows the vapor to condense at more areas, allowing for a more refined seperation of liquids
why is cysteine's configuration R?
it has sulfur in its R group so there is a change in priority
Phosphoric Acid (H3PO4) is an excellent buffer because
it has three hydrogens with pKa values that span nearly the entire pH scale
what makes glycine unique?
it is achiral
why is vacuum distillation useful?
it is good for high boiling points so as to not degrade the products, the increased pressure makes the solutions boil at lower temps
when two equivalents of alcohol are added to an ketone, what is the product
ketal
Due to the acidity of the a-hydrogen, aldehydes and ketones exist in solution as a mixture of two isomers
keto form and the enol form
secondary alcohols can be oxidized to
ketones
electrophilicity is a _____ property where acidity is a ______ property
kinetic thermodynamic
if a reaction is reversible, the _____ product can be converted to the ______ product
kinetic (less stable) thermodynamic (more stable)
azimuthal quantum number
l
lactones vs lactams mneumonic
lactAM is a cyclic AMide lactone is a cyclic ester
amides that are cyclic are called
lactams
sp hybrid shape
linear
cyclic carboxylic acids are named
list the cycloalkane with the suffix "carboxylic acid"
when naming amides, how are substituents on the nitrogen named?
listed as prefixes with the letter "N-"
soaps are basically _________ chain _________
long chain salts
during UV spec, the smaller the difference between HOMO and LUMO the ______ the the wavelengths a molecule can absorb
longer
the closer the HOMO and LUMO are, the
longer the wavelength
oxidation
loss of electrons, increase in oxidation number in organic chem it is easier to view oxidation as increasing the number of bonds to oxygen or other heteroatoms (atoms besides carbon and hydrogen)
injected compounds into gas chromatography must be volatile, meaning......
low melting point, subliminal solids or vaporizable liquids
the alpha state of the nuclei is the ________ energy stage
lower
alpha state= _____ energy beta state= _____ energy
lower higher
magnetic quantum number
m sub l
spin quantum number
m sub s
gas chromatography may be combined with
mass spectrometry
IR spectroscopy
measures absorption of infrared light, which causes molecular vibration (stretching, bending, twisting, and folding)
what does NMR spec measure and what is it good for?
measures alignment of a nucleus within a magnetic field, good at finding connectivity by looking at hydrogen
acid dissociation constant (Ka)
measures the strength of an acid in solution
formaldehyde and formic acid both refer to molecules with ______ as the parent chain
methane
alkanes with 1 Carbon to 12 Carbons
methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane
formic acid
methanoic acid
SN2 reactions favor ______ or ____ carbons are preferred over _______ carbons, and _______ carbons wont react
methyl or primary secondary tertiary
mesylates are prepared using
methylsulfonyl chloride and an alcohol in the presence of a base
hybrid orbitals are formed by
mixing different types of orbitals
enantiomers
molecules that are mirror images of each other EVERY chiral center in the molecule is opposite
bonding orbitals are ______ stable than anti bonding orbitals
more
multiple extractions with smaller volumes of fresh water is ______ effective than one large extraction
more
the more oxidized the functional group, the _____ reactive it will be in both oxidation-reduction and nucleophile-electrophile reactions
more
the Hydrogen of the phenol alcohol is ________ acidic than normal alcohols. why?
more the resonance of the aromatic ring causes increased stability of the conjugate base
anti conformation
most favorable of staggered conformations, two largest groups are 180 rotated from eachother
are there more keto or enol tautomers in solution?
much more keto
principal quantum number
n
a proton's peak is split into ______ sub peaks, where n is the number of protons that are three bonds away from the proton of interest
n+1
five categories of amino acids
non polar nonaromatic, aromatic, polar, negatively charged (acidic), positively charged (basic)
ester naming
name group off of the Oxygen as a substituent and then name the carboxylic acid with -oate ending Picture shown is ETHYL ETHANOATE
non symmetric anhydrides are named by
naming both carboxylic acids (minus "acid") and then adding anhydride
when anhydrides are asymmetrical, name them by
naming the two chains alphabetically followed but the word anhydride
tertiary alcohols can be oxidized by
never, they cannot be oxidized without breaking a carbon-carbon bond
are all quinones aromatic?
no
racemic mixtures have _______ optical activity
no
will Carbon-12 appear in NMR spec?
no
physical properties
no change in the composition of matter examples: MP, BP, solubility, odor, color, density
symmetric stretches do not appear on IR spectra because they involve _____
no net charge in dipole movement
staggered newman projection
no overlap of atoms along the line of sight
carboxylic acid derivatives of higher reactivity can form derivatives of lower reactivity but not vice versa. esters form anhydrides?
no, anhydrides are more reactive than esters
is conversion from an ester to an anhydride possible by a nucleophilic reaction?
no, that would be going from less to more reactive
During the Gabriel synthesis, phthalimide serves as the; Nucleophile Base Leaving group Electrophile
nucleophile
HCN is a class example of a _______
nucleophile
How do the definitions of nucleophile and electrophile differ from those of Lewis Acids and Lewis Base?
nucleophile and electrophile are kinetic Lewis Acids and Lewis Base are thermodynamic
describe the SN2 backside attack?
nucleophile attacks the carbon from the opposite side as the leaving group, inverting the configuration
briefly describe the mechanism of nucleophilic acyl substitution reactions
nucleophile attacks the carbonyl carbon and then the leaving group leaves(H2O)
How must the nucleophile and leaving group be related in order substitution reaction to proceed?
nucleophile must be a stronger base, LG must be more stable and less reactive,
_______ tend to have lone pairs of pi bonds that can be used to form ________ bonds to ________
nucleophiles covalent electrophiles
carbonyls can act as either _______ or ________
nucleophiles (condensation reactions) electrophiles (nucleophilic addition reactions)
many of the reactions in which carboxylic acids participate proceed via and single mechanism: ________.
nucleophilic acyl substitution
most notable examples of organic phosphates
nucleotide triphosphate (ATP or GTP) and DNA
nuclei with _______, ________, or both will have a magnetic moment when placed in a magnetic field
odd mass numbers, odd atomic numbers, or both
chair flip
one chair conformation is converted to the other briefly passes through the half chain conformation all axial groups become equatorial all equatorial groups become axial dashed lines remain dashed wedges remain wedges
how does enol get its name?
one from Carbon=Carbon double bond ol from the alcohol
two examples of cyclic anhydrides
ophthalmic and succinct anhydrides, which aris from intramolecular condensation or dehydration of diacids
within each subshell there may be multiple ______
orbitals
orbital hybridization
orbitals involved in covalent bonding in an atom are hybridized so that they are identical in properties, and those properties are intermediate to the properties of the original orbitals
the ______ layer is usually on the top and the _______ layer is usually on the bottom
organic layer on top aqueous on the bottom ****though it can be different, it all comes down to density
organic phosphates vs inorganic phosphates
organic phosphates are bound to Carbon
Ortho, Meta, Para
ortho (1,2) meta (1,3) para (1,4)
what is the name of the smallest dicarboxylic acid?
oxalic acid (ethandioic acid)
what are the first 6 straight chain dicarboxylic acids in order?
oxalic, masonic, succinic, glutamic, adipic, and pimelic acids
alpha hydrogen acidity
oxygen pulls some of the electron density out of the bond between the alpha carbon and alpha hydrogens, weakening them and making these hydrogens acidic
how is pka defined and what does low pka indicate
pKa=-logKa low pKa = increased acidity
amino acids undergo condensation reactions to form
peptide bonds
IR spectra are plotted as ___________________ versus _______ ______________
percent transmittance vs. wave number (1/wavelength)
stability of the conjugate base is determine why what factors?
periodic trends (electronegativity) size of the anion resonance
what trends increase electrophilicity?
positive charge, better LGs
what are the most acidic oxygens
phenols
how are quinones usually produced
phenols treated with oxidizing agents
aromatic amino acids
phenylalanine, tyrosine, tryptophan
phosphoric acid is sometimes referred to as
phosphate group or inorganic phosphate
phosphate is found in the ________ bonds that link the sugar moieties in DNA
phosphodiester
Vitamin k1 (________) and vitamin K2 (________) are examples of biochemically relevant quinones
phylloquinone menaquinones
boiling point and melting point are examples of ________ properties
physical
gabriel synthesis requires
potassium pthalimide diethyl bromomalonate basic conditions
if a solvent is not given, assume that the reaction occurs in a ______ solvent.
polar polar solvents are able to dissolve nucleophiles, which is necessary for these reactions to occur
the stationary phase or absorbent is usually a __________
polar solid
_____, ______, and ______ amino acids are all hydrophilic and form H bonds with water in aqueous solution
polar, acidic, and basic
column chromatography utilizes
polarity, size, or affinity to separate compounds based on physical and chemical characteristics
polypeptides
polymers of amino acids that make up proteins
acetone is significant as the smallest ketone, its IUPAC name is what?
popanone
esterification occurs most rapidly with ______ alcohols
primary
aldehydes will be reduced to ______ and ketones will be reduced to ______
primary alcohol secondary alcohol
LiAlH4 will reduce carboxylic acids to
primary alcohols
carboxylic acids can be reduced to _______________ by the use of LIAlH4
primary alcohols
what alcohols can be synthesized into carboxylic acids
primary alcohols only
only ______ and ______ amines will undergo condensation reactions to form amides because..........
primary and secondary the loss of a hydrogen from the nucleophile is necessary for this reaction to proceed
Cahn-Ingold-Prelog priority rules
priority is given by looking at the atoms connected to the chiral carbon or double-bonded carbons - whichever has the highest atomic number gets highers priority - if there is a tie, one moves outward from the chiral carbon or double bond until the tie is broken
propionic acid
propanoic acid
propanoic acid common name
propionic acid
in addition to making alcohols good leaving groups, tosyl and mesyl groups can also be used as
protecting groups when we do not want alcohols to react
Bronsted-Lowry base
proton acceptor
Bronsted-Lowry acid
proton donor
cyclobutane exists mainly in what configuration?
puckered V shape
treatment of phenols with oxidizing agents produces compounds called
quinones
when + and - enantiomers are present in equal proportion the mixture is said to be
racemic
the products of streaker synthesis are a ______ mixture
racemic L and D amino acids are created
what kind of mixtures/molecules are optically inactive?
racemic mixtures, miso compounds, chiral compounds
magnetic quantum number (m sub l)
ranges from -l to +l for a given subshell. determines the orbital in which the electron resides
azimuthal quantum number (l)
ranges from 0 to n-1. 0, 1, 2, and 3 correspond to s, p, d, and f subshells respectively energy also increase as the azimuthal number increases
kinetic produces form ________ and are _________ stable
rapid, less
Sn2 rate law
rate = k[substrate][nucleophile]
rate law for SN1
rate=k[alkyl group containing leaving group]
how can you synthesize esters?
reacting carboxylic acids with alcohols under acidic conditions
chemical properties
reactivity of molecule, resulting in a change in composition: generally attributable to functional groups in a molecule
Na+, LiAlH4, and Aluminum are examples of good ______ agents
reducing
The conversion of ubiquinone to ubiquinol requires what type of reaction?
reduction
TMS provides a
reference peak at chemical shift of 0
nucelophile strength is based on ________________ and is therefore a _____ property
relative rates of reaction with a common electrophile kinetic
conformational isomers differ by
rotation around a single (sigma) bond
Within one principal energy level, which sub shell has the least energy? s p d f
s
when long chain carboxylic acids react with NaOH or KOH, a ______ called _______ is formed
salt soap
C=O IR spec peak
sharp peak around 1750
carboxylic acid OH IR spec peak
sharp peak at 3000 cm-1
NH peak on IR spec
sharp peak at 3300 cm-1
n describes what organizational level? l describes what organizational level? m(l) describes what organizational level? m(s) describes what organizational level?
shell subshell orbital ------
TLC stationary phase is
silica gel, a polar solid
High Performance Liquid Chromatography (HPLC)
similar to column chromatography but uses sophisticated computer-mediated solvent and temperature gradients
amides are names
similar to esters except that a the suffix becomes "-amide" substiuents attached to the nitrogen are labeled with a capital N-
three types of distillation
simple, vacuum, fractional
why is a single bond stronger than a pi bond?
single bonds have more overlap
decarboxylation occurs through a ___________ in its transition state
six membered ring
Principle quantum number n is essentially a measure of
size
n describes ______ l describes ______ m(l) describes ______ m(s) describes ______
size shape orientation spin
what is the best chromatographic technique to seperate large molecules from small molecules?
size exclusion chromatography
thermodynamic products form ________ and are _____ stable
slow, more
hydration reactions generally proceed slowly but can be increased by adding
small amount of catalytic acid or base
during size exclusion, the _________ compounds move more slowly through the column
smaller
More acidic molecules will have a ____ pKA
smaller (or even negative)
filtration isolates a _____ (residue) from a ______ (filtrate)
solid from a liquid
the mobile phase runs through the stationary phase and is usually a ________ that elutes the sample through he sample phase
solid or gas
column chromatography mobile phase
solvent that travels by gravity
s orbitals are what shape?
spherical
good leaving groups are able to
stabilize the extra electrons
conjugation makes _____ compounds because of the presence of multiple _________
stable resonance structures
if an isomer has the same connectivity is a _________ and if it doesn't have the same connectivity it is a ________
stereoisomer structural/constitutional isomer
Diastereomers
stereoisomers that are not mirror images differ in some but not all chiral centers
Diastereomers
stereoisomers that are not mirror images, differ in some but not all chiral centers
two ways of synthesizing amino acids?
strecker and gabriel synthesis
strecker synthesis compared to gabriel
strecker is more elegant, more simple and efficient
Sn2 reactions require what?
strong nucleophiles and non-sterically hindered electrophiles
what are the least similar of all isomers?
structural/constitutional isomers
why is glycine not optically active?
the alpha carbon is not chiral due to having two Hydrogen atoms
enol and keto are
tautomers
polar amino acids
tend to have terminal groups containing oxygen, sulfur, and nitrogen serine, threonine, asparagine, glutamine, cysteine
negatively charged (acidic) amino acids
terminal carboxylate anions in their R groups aspartatic acid, glutamatic acid
Sn2 reactions won't occur with _______ substrates
tertiary
would an SN! reaction happen more quickly on a primary or a tertiary carbon?
tertiary the more substituted it is, the more stable the carbocation will be
SN1 reactions favor _____ or _____ carbons
tertiary or secondary tertiary and secondary carbons will be more stable carbocation
sp3 hybridization
tetrahedral
alcohols may be protected from reactions by the reversible reduction to ______________
text-butyl ethers
angle strain results when
the bond angles deviate from their ideal values by being stretched or compressed
what bond is broken during a retro-aldol reaction
the bond between the alpha and beta carbons of the carbonyl
resonance
the bonding in molecules or ions that cannot be correctly represented by a single Lewis structure
why is the kinetic formation of an enolate quicker than the thermodynamic product of an enolate
the carbon that is deprotonated to create the kinetic product is less hindered and therefore can be accessed by the base more easily
affinity chromatography
the column is made to have high affinity for a compound by coating the beads with a receptor or antibody to the compound
the amount of rotation when looking at plane-polarized light depends on what?
the concentration of the optically active compound and the length of the tube through which light passes
induction
the distribution of charge across sigma bonds
the principal quantum number n represents
the energy level of a given electron in an atom
when naming diols
the entire hydrocarbon name is preserved and diol is added to the end, name locations of all hydrocarbon groups i.e. ethane-1,2-diol
conjugation
the presence of alternating single and multiple bonds
where are the acidic hydrogens located on B-dicarboxylic acids
the hydrogen of the hydroxyl and on the alpha carbon
structural isomers (constitutional isomers)
the least similar of isomers, the only this the same between structural isomers is their chemical formula
nitrogen and nitrogen based functional groups act as good nucleophiles due to
the lone pair on the Nitrogen atom
EWG effect on NMR shifting
the more electronegative groups present, they pull electron density away from the protons. The more electron density that is pulled away from the proton, the more deshielded it will be and the further downfield the proton will appear
what does the conjugate base's stability have to do with deprotonation of acids
the more stable the conjugate base, the easier to the hydrogen can leave and the stronger the acid
when two possible enolates are possible, which is the the favored?
the most substituted
cyanohydrins gain their stability by
the newly formed C-C bond
oxidation reactions tend to fature and increase in _________ and oxidizing agents often contain ________ bonded to a large number of ________ atoms
the number of bonds to oxygen metals oxygen
the height of each peak in NMR is proportional to
the number of protons it contains
what is the key difference between nucleophilic addition to an aldehyde or ketone and nucleophilic acyl substitution?
the presence of a good leaving group in carboxylic acids
NMR spec is useful for determining
the structure of a compound, including functional groups
organic chemistry
the study of all chemicals containing carbon
distillation separates liquids based on
their boiling points
tertiary alcohols are oxidized with difficulty because
there is no hydrogen attached to the carbon with the hydroxyl group
what makes soaps special?
they are amphipathic, the polar head organizes itself on the outsdie of the micelle and the nonpolar tails are on the inside, nonpolar molecules such as grease and dirt can dissolve in the interior of the molecule, while the micelle as a whole can dissolve in water
adjacent phosphate groups on a nucleotide triphosphate experience a large amount of repulsion becasue
they are negatively charged
How can aldehydes or ketones be protected using alcohols?
they can be reacted with two equivalents of an alcohol or a diol to form acetals or ketals, which serve as protecting groups
how quickly do tertiary carbons react in an SN2 reaction
they don't react, too much steric hinderance
why would alkanes and hydrogen ions never serve as leaving groups?
they form very reactive, strongly basic anions
what makes phosphoric acids good buffers
they have 3 hydrogens all with different pKas
rotation of double and triple bonds
they hinder rotation, locking the atoms into position
Why do esters have lower boiling points than carboxylic acids?
they lack H bonding
why are carboxylic acids good acids?
they like to give away protons and when they do give away protons the negative charge is stable because it is by two oxygen atoms
what must be true about the two solvents used for an extraction to work?
they must be immiscible
carboxylic acids characteristics
they're good acids, they like to give away protons and when they do give away protons the negative charge is stable because it is by two oxygen atoms they also participate in hydrogen bonding, which results in high intermolecular forces and high boiling points
with _____ bonds to oxygen atoms, carboxylic acids are some of the most oxidized functional groups encountered in organic chemistry
three
saponification of one triacylglyceron results in what?
three soap (fatty acid) molecules and one glycerol
tosylates are derived from
toluenesulfonic acid
in aprotic solvents, nucleophilicity of halogens (I, Cl, F, Br) decreases in this order
top to bottom F>Cl>Br>I this is because there are no protons to get in the way of the attacking nucleophile. In aprotic solvents, nucleophilicity relates directly to basicity
highest total energy conformation
totally eclipsed
what is the conformation called when the two highest priority groups are 0 degrees apart?
totally eclipsed
reverse phase chromatography uses what?
uses a nonpolar card with a polar solvent
in what way is gas chromatography different from all other techniques discussed?
uses gases
many common oxidizing and reducing agents are _______ metals, this is because _________
transition they take many different oxidation states
UV spectra are plotted as
transmittance or absorbance vs. wavelength
what is the storage form of fat in the body
triglycerides
sp2 hybridzation shape
trigonal planar
size of single double and triple bonds
triple bonds are shorter than double, and double are shorter than single
Strength of single, double, and triple bonds
triple bonds are stronger than double, and double are stronger than single
rank the following orbitals decreasing order of strength: sigma bonds, pi bonds, double bonds, triple bonds
triple---> double---> sigma---> pi
butanoic anhydride can be formed by
two butanoic acid molecule coming together and giving off H2O
anhydrides are created via the condensation of
two carboxylic acids
anhydride formation
two carboxylic acids come together and give off H2O
a hydroquinone is a benzene ring with ______________. A hydroxyquinone contains ________
two hydroxyl groups two carbonyls and a variable number of hydroxyl groups
extraction combines
two immiscible liquids, one of which easily dissolves the compound of interest
Pi bonds are formed by which of the following orbitals? two s-orbitals two p-orbitals one s- and one p-orbital two sp2 hybridized orbitals
two p orbitals
pi bonds are formed when
two p orbitals lining up parallel (side to side) and their electron clouds overlapping, forming a bonding molecular orbital
all forms of chromatography use __________ to separate compounds based on physical or chemical properties
two phases (mobile and stationary)
ubiquinone can be reduced to form
ubiquinal
SN1
unimolecular nucleophilic substitution 2 steps -leaving group leaves forming a carbocation -nucleophile attacks carbocation first order so the rate only depends on the concentration of the substrate
in polar parotid solvents, nucleophilicity increases _____ the periodic table
up
what is the purpose of a mesylate or tosylate?
used to convert an alcohol into a better leaving group, also can be used as a protecting group
if we were given a solution with a BP of 156C and one with a BP of 204C, which distillation technique would be best
vacuum because of the high temps
carboxylic acid smell
very strong and unpleasant
what happens during an aldol reaction when there are multiple kinds of aldehydes or ketones?
we cannot control which will act as nucleophiles and electrophiles, so we get a mixture of products
_____ bases make good leaving groups
weak
what are the features of good leaving groups?
weak bases, resonance, can stabilize electrons
an acid-base reaction will only proceed if the products that will be formed are _____ than the original reactants
weaker
in Fischer projections the horizontal lines are ______ and the vertical lines are _____
wedges dashes
Transesterification
when alcohol acts as a nucleophile and displaces the esterifying group on an ester one ester is transformed into another
under what conditions will carboxylic acid spontaneously decarboxylate?
when heated
if the stability of various resonance forms differ, the true electron density
will favor the most stable form
NMR spectra are calibrated using TMS, which has a chemical shift of ______.
zero
