13. Alcohols and Carbonyl Compounds

Both NaBH₄ and NaBD₄ are commercially available, and D₂O is common and inexpensive. Show how you would synthesize the following labeled compounds, starting with butan-2-one.

(a)

In which step(s) of the hydride reduction of an ester does the compound undergo reduction? (Hint: Count the bonds to oxygen.)

Predict the product of the following reaction sequences.

(a)

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

(a) octan-1-ol

Propose a mechanism for the reduction of octanoyl chloride by lithium aluminum hydride.

What would have been the product of the preceding reaction with LiAlH₄ if the keto group had not been protected?

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Predict the products of the following reactions:

(a)

(b)

Predict the products you would expect from the reaction of LiALH₄ followed by hydrolysis with the following compounds. You may assume that these reactions take place in methanol as the solvent.

(c) Ph-COOH

Compounds containing deuterium (D = ²H) are useful for kinetic studies and metabolic studies with new pharmaceuticals. One way to introduce deuterium is by using the reagent LiAlD₄, equivalent in reactivity to LiAlH₄. Show how to make these deuterium-labeled compounds, using LiAlD₄ and D₂O as your sources of deuterium, and any non-deuterated starting materials you wish.

(c) CH₃CD₂OD

What amides would you react with LiAlH₄ to form the following amines?

a. benzylmethylamine

b. ethylamine

c. diethylamine

d. triethylamine

How can the following compounds be prepared from the given starting materials?

b.

Show how you would synthesize the following alcohol by reducing appropriate carbonyl compound.

a. heptan-1-ol

What products are obtained from the reaction of the following compounds with LiAlH₄ followed by treatment with dilute acid?

c. methyl benzoate

d. pentanoic acid

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

(c) 1-phenylbutan-1-ol

(d)