Question 1

How many equivalents of methyl Grignard ($$\mathrm{CH_3MgBr}) $$are required to fully react with ethyl acetate ($$\mathrm{CH_3COOCH_2CH_3}) to $$convert it to a tertiary alcohol?

Accepted Answer

2

Question 2

Which of the following carbonyl compounds will form the most stable hemiacetal upon reaction with methanol?

Accepted Answer

Benzaldehyde

Question 3

Which of the following carbonyl compounds could NOT be used to prepare N-methylaniline via reductive amination?

Accepted Answer

Benzophenone

Question 4

Which of the following carbonyl compounds will produce the highest concentration of hydrate in aqueous solution?

Accepted Answer

Trichloroacetaldehyde ($$\mathrm{CCl_3CHO})$$

Question 5

What is the product of the reaction between cyclohexanone and ethylene glycol in the presence of acid?

Accepted Answer

A cyclic acetal

Question 6

Which set of reagents would you use to convert a nitrile ($$\mathrm{R-CN}) to a $$primary amine ($$\mathrm{R-CH_2NH_2}$$)?

Accepted Answer

$$\mathrm{1. $$LiAlH_4$$, 2. H_2O}$$

Question 7

Which of the following best describes the mechanism of reductive amination?

Accepted Answer

Nucleophilic addition of an amine to a carbonyl, followed by reduction of the imine intermediate

Question 8

Which of the following sequences would convert benzaldehyde to benzyl alcohol?

Accepted Answer

$$\mathrm{1. $$NaBH_4$$, 2. H_2O}$$

Question 9

A student attempts to synthesize a tertiary alcohol by reacting 2 equivalents of methyl Grignard ($$\mathrm{CH_3MgBr}) $$with methyl benzoate ($$\mathrm{C_6H_5COOCH_3}). $$What is the major organic product?

Accepted Answer

1,1-Dimethyl-1-phenylmethanol

Question 10

Which of the following best explains why trichloroacetaldehyde forms a hydrate more readily than acetone?

Accepted Answer

The electron-withdrawing chlorine atoms stabilize the hydrate by increasing the electrophilicity of the carbonyl carbon.

Question 11

Which of the following is the correct mechanism for the acid-catalyzed formation of an acetal from a ketone and an alcohol?

Accepted Answer

Protonation of the carbonyl, nucleophilic attack by alcohol, formation of a hemiacetal, protonation and loss of water, second alcohol attack, deprotonation to give acetal

Question 12

Which of the following synthetic routes would convert cyclohexanone to cyclohexanone oxime?

Accepted Answer

$$\mathrm{1. NH_2OH, 2. H^+}$$

Question 13

A chemist wants to protect a carbonyl group during a multi-step synthesis. Which reagent pair would be most appropriate?

Accepted Answer

Ethylene glycol and acid catalyst

Question 14

Which of the following statements about Grignard reagents is TRUE?

Accepted Answer

They react with esters to give tertiary alcohols after two equivalents are added.

Question 15

Which of the following is the correct order of reactivity toward nucleophilic addition: formaldehyde, acetone, benzaldehyde?

Accepted Answer

Formaldehyde \u003e acetone \u003e benzaldehyde

Question 16

Which of the following best describes the product of the reaction between an aldehyde and a primary amine under acidic conditions?

Accepted Answer

Imine

Question 17

A student treats acetophenone ($$\mathrm{C_6H_5COCH_3}) $$with excess methylamine and sodium cyanoborohydride. What is the major product?

Accepted Answer

N-methyl-1-phenylethylamine

Question 18

Which of the following is a correct sequence for the synthesis of a tertiary alcohol from an ester?

Accepted Answer

$$\mathrm{1. 2~equiv~Grignard~reagent, 2. H_2O}$$

Question 19

Which of the following best explains why acetals are commonly used as protecting groups for carbonyls in organic synthesis?

Accepted Answer

They are stable to base and nucleophiles but can be removed under acidic conditions.

Question 20

Which of the following is the correct product of the reaction between benzaldehyde and hydroxylamine ($$\mathrm{NH_2OH}$$)?

Accepted Answer

Benzaldoxime

Organic Chemistry II Practice Exam Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard