Oraganic chem 2 Lab Midterm
what reagents would accomplish a hydrocarbon-oxidation of an alkene ?
1. BH3/THF and 2. NaOH, H2O2, H2O
according to the Markovnikov's rule of the electrophillic addition to an alkene, the electrophile, usually a proton, is more likely to add to the _____ in a double bond. This arrangement places the intermediate carbocation on the _______, which stabilizes it with the presence of ______. In the major product of a reaction following Markovnikov's rule, the _____ will then end up on the more-substituted carbon in a double bond
1. Less substituted carbon 2. more substituted carbon 3. more substituents 4. nucleophile
identify each function group 1. RCOR' 2. RCOOR' 3. RCONR'R'' 4. RCOOH 5. RCOH
1. ketone 2. esther 3. amide 4. carboxylic acid 5. aldehyde
how many reducing equivalents are present in each unit of sodium borohydride
4
what are the reasons to determine the melting point of a sample in a melting point apparatus ?
Assessment of the sample's purity Identification of an unknown sample
Which statement is related to the Diels-alder reaction? a) it is very stereospecific b) molecular distortion takes place c) cyclic diene react very slowly compared to linear chain dienes d) addition of maleic anhydride to cyclopentadiene causes diene and dienophile to produce different products
C
which is unreactive in hydride reduction with NaBH4
Carbon attached to 2 oxygens
what does H2O/H2SO4 add to a molecule
OH and rearranges the bonds (review question 12)
which is an example of a carbonyl compound?
RCHO (aldehydes), carboxylic acid RCOOH, ketones (R2=O), esters (RCOOR'), and Amides (RCONR'₂)
what is the mechanism for the williamson ether synthesis
SN2 mechanism (reaction happens in one step or simultaneously)
what is cycloaddition
a chemical reaction where two or more unsaturated molecules form a cyclic product
what is an islolated double bond
a molecule in which more than one single bond seperates two double bonds
which task should be carried out before using a round bottom flask at the lab bench
a propper support, such as a cork ring, should be set in place
what does concerted mean?
a reaction where all changes in bonding occur simultaneously
which of the following functional groups is indicated by a strong and broad infrared absorption around 3300 cm -1 ?
alcohol
what does conjugated mean
alternating double and single bonds especially between carbon molecules
the regioselectivity and stereospecificity in the hydroboration-oxidation of an alkene is best described as?
anti-Markovnikov orientation and syn-addition
when drying agent is added to a sloution, how is ti determined that enough drying agent has been added
any newly added drying agent remains powder, isntead of clumping up.
what is a heteroatom in an organic compound
anything that is not a carbon or hydrogen. In organic, that can be nitrogen, oxygen, sulfur, or phosphorus
when working in a fume hood what is the best position of the hood hash
as low as possible, no more than halfway
what are the characteristics of a dienophile?
at least one double of triple bond acts as electrophile
dienes with bonds seperated by exactly one sigma bond are classified as?
conjugated
what does a conjugated diene react with to form a cyclohexene?
dienophile
what are the optimal conditions to achieve a hydration of 1-hexene
dilute aqeous H2SO4
how are carbonyl groups characterized
double bond between carbon atoms and oxygen atom C=O
what are the characteristics of ethers
general structure is ROR' where R and R' can be the same of different hydrocarbon chain Oxygen is sp3 hybridized
what is 1,4-pentadiene the perfect example of?
isolated double bond
what does adding BH3/THF and H2O2/OH- do to a molecules.
it first adds BH2 and then replaces it with OH
why is sodium borohydride an important reagent when reducing a ketone
it is a good source of a hydride ion (H+)
what are the characteristics of a diene?
organic compounds two double bonds
what cannot participate in a diels-alder reaction
pentanes
what are good characteristics of a good recrystallization solvent
recrystallization happens in a cold solution therefore solvent must dissolve sample well at high temps but poorly at low temps it should not be an organic solvent with a low boiling point
what items can be used to control boiling when heating liquid in a round bottom flask
stir bar with a stirring plate or a magnetic stirrer or boiling chips
how do we know that 4-methy-1,3-heptadiene
the 1,3 bonds are seperated by exactly one sigma bond
when should you replace your gloves in an organic lab?
when you see any visible tear in the gloves
