Help with Alcohol Synthesis

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1

What is the product of a hydroboration–oxidation reaction with 1-hexylcyclohexene?

2-hexylcyclohexanol

CORRECT

1-hexylcyclohexanol

0

3-hexylcyclohexanol

0

Hexylcyclohexane

0

Cyclohexane

0

Explanation

This reaction is an electrophilic addition reaction with an alkene. This is one of many alkene addition reactions that can add an -OH group onto your starting material. The key aspect of an hydroboration-oxidation reaction is the anti-Markovinikov addition to the double bond. The -OH group should be on the least substituted of the two carbons that originate from the double bond. In light of this information, the answer is 2-cyclohexanol.

2

2butanone

What is the product when the given starting compound is reacted with lithium aluminum hydride and acid?

2-butanol

CORRECT

1-butanol

0

2-butanone

0

1-butanone

0

No reaction will occur

0

Explanation

This reaction involves a very strong reducing agent in lithium aluminum hydride, . LAH converts ketones, aldehydes, esters, and acid chlorides into alcohols. This reaction changes the carbonyl group into a hydroxyl group. As a result, the final answer is 2-butanol.

3

What reagents are required to efficiently form a tertiary alcohol with two of the same substituents in only two steps?

An ester reacted with 1) 2RMgBr and 2) H3O+

CORRECT

An ester reacted with 1) 2RLi and 2) NH3

0

An ester reacted with 1) RMgBr and 2) H3O+

0

An acid chloride reacted with 1) 2RMgBr and 2) hexane

0

An ester reacted with: 1) excess ethanol and 2) H3O+

0

Explanation

This is an example of a Grignard reaction that requires the use of an ester or acid chloride, and more than one equivalent of an organometallic. The second step would be to react the product of the first step in an acidic source.