13. Alcohols and Carbonyl Compounds

Show how you would accomplish the following synthetic transformations. You may use any necessary reagents.

(a) N-ethylbenzamide → benzylethylamine

(b) ethyl benzoate → N-ethylbenzamide

Suggest carbonyl compounds and reducing agents that might be used to form the following alcohols.

(b) 1-cyclohexylpropan-1-ol

Suggest the most appropriate method for each of the following laboratory syntheses. In each case, suggest both a chromium reagent and a chromium-free reagent.

(a) butan-1-ol → butanal, CH₃CH₂CH₂CHO

(b) but-2-en-1-ol → but-2-enoic acid, CH₃CH=CH–COOH

(c) butan-2-ol → butan-2-one, CH₃COCH₂CH₃

Sodium triacetoxyborohydride, NaBH(OAc)₃, is a mild reducing agent that reduces aldehydes much more quickly than ketones. It can be used to reduce aldehydes in the presence of ketones, such as in the following reaction:

(b) Propose a mechanism for the reduction of an aldehyde by sodium triacetoxyborohydride.

Predict the products you would expect from the reaction of NaBH₄ with the following compounds. You may assume that these reactions take place in methanol as the solvent.

(d)

Predict the products you would expect from the reaction of NaBH₄ with the following compounds. You may assume that these reactions take place in methanol as the solvent.

(a) CH₃–(CH₂)₈–CHO

Show how you would synthesize the following compounds from the appropriate carboxylic acids or acid derivatives.

Suggest the most appropriate method for each of the following laboratory syntheses. In each case, suggest both a chromium reagent and a chromium-free reagent.

(f) 1-methylcyclohexanol → 2-methylcyclohexanone (several steps)

What is the product of the reaction?

Predict the product of the following reductions.

(d)

Identify A through O:

Show how you would accomplish the following transformations. You may use any additional reagents you need.

(c)

Draw the products of the following reactions. Indicate whether each reaction is an oxidation or a reduction.

a.

b.

c.

Predict the major products of the following reactions.

(f)

Predict the products of the following reactions.

(c) 1-methylcyclohexanol + H₂SO₄, heat

(d) product of (c) + H₂, Pt