Functional Groups & Reactions

Answer A

Passage A

Tyr, Phe, Trp, Pro?

Pro

Gabriel Synthesis // Malonic ester synthesis

B. Gabriel Syn results in a mixture of enantionmers, and the catalyst used in the Hajos Parrish reaction is a single enantiomer

C. GS results in the S enantiomer, and the catalyst used in the HP reaction is R enantiomer

D. (flip the S and R order in answer C)

Answer: B

Vinyl vs allyl group

B. By using a resolving agent to create a mixture of diastereomers, which can be separated due to ahving different chemical properties

D. Separate the mixture of enantiomers obtained fromt eh reaction using column chromatography with a chiral stationary phase

Answer: D

3

Answer: 4

Adol condensation

carbon carbon bond forming reactions where two carbonyl compoudns (ketones and/or aldehydes) are joined together by nucleophilic additon to form the adol product.

Adol condensation true or false based on a passage

1. reaction ahs two carbonyl compounds as substrates

2. reaction involves protonation of a bcarbon for elimination

3. reaction has resonance stabilized intermediate

4. reactions yields a conjugated product

1. true

2. flase

3. true

4. true

Answer A

Answer D

Note: ALL amino acids EXCEPT cysteine has a S configuration. The S form of most amino acids is the L form (except cys R-L)

so answer is B

Clockwise—> R—> but H is wedge in front—→ flip—→ S configuration

This above is compound A

This is compound E

Answr D

Abnswer B

nucleophilic addition, nucleophilic elimination, nucleophili acyl substitution, Sn2?

nucleophilic acyl sub

Carbonyl carbon in B is more electrophilic than Carbonyl carbon in compound D

Or

Carbonyl carbon in Compound B is less sterically hindered than D

2

Lactonization

intramolecular reaction between alcohol and carboylic acid to form lactone ( cyclic ester)

Lactamization

intramolecular condensation reaction between amine and carboxylic acid to form lactam (cyclic amide)

What is the chemical transformation?

Hydrolysis, lactonization, reduction, or lactamization?

Answer: D

Lovastatin

Note electronic effect vs steric effect

aldol condensation or aldol addition?

adol addition

Answer D

Just state what molcule is deprotonated

Water (H2O)

Answer: B

A. Add a fractionating column

B. palce receiving flask in an ice bath

D. Connect distillation setup to a vacuum

Answer A

Ester, Anhydride, Amide or Enamine

Amide

blactam rings —> angle strain (less than 109.5º)

or

B lactam can participate in more resonance

ANswer; A

Cyanohydrin

Answer D

C. The hemiketal—OH group cannot be protonated under basic conditions to make a good leaving group for the ketal to form

D. The hemiacetal—Oh group cannot be protonated udner basic conditions to make a good leaving group for the acetal to form

What issue of the protection group formation?

L, D, R, S

S configuration

(lets focus on aldehyde)

a branched aldehyde with same molecular weight

Answer: D

Carboxyl group

Functional group examples

Answer C

will the product (Ethyl hexanoate) or Hexanoic acid distill first?

Product will distill first because hexanoic acid has higher boiling point

A. base catalyzed aldol condensation

B. Decarboxylation

C. Oxidation with NaBH4

D.Reduction with LiAlH3

Answer: D

L, D, or Mix?

Mix

15 minute mark

boiling point (lowest to highest)

ethane < Acetaldehyde < ethanol + ethyl acetate < Acetic acid

Number 1

Oxidation of alchohols

2 only

Answer D

Condensation, Neutralization, Elimination, Hydrolysis

Neutralization

A. a-carboxylate stablizes a-amine through charge charge interactions

B. a-carboxylate withdraws electrons from the a-amine due to inductive effect

C. protonated a-amine is stabilized through resonance

Answer B

Enamine or imine?

Enamine

A,B, or C?

Answer compound C

Yes because protected alcohol group is unreactive underoxidizing conditions

Protecting groups

A. halogenated products have a lower melting point than ether-containing products

B. compounds with hydrogen bond donors do not have the highest melting points

C. an increase in alkyl groups increases the melting point of the product.

Answer C

A. reduction of amine nitrogen

B. Carboxylation of amine nitrogen

C. Acylation of hydroxylamine nitrogen

D. Oxidation of the hydroxylamine nitrogen

Answer C

Answer A

Lower, because they cannot form hydrogen bonds with each other

Answer D

3 only

basic catalyst for condenstion, eliminartion, or both?

Answer both

fatty acyl group or fatty acid

fatty acyl group

lactone group

materials for strecker synthesis

Answer B

Answer D

anhydride can’t form because…

it doesn’t have a beta carbonyl

Answer B