Question

Question: What carbonyl starting materials are needed to prepare each compound using a directed aldol reaction?

Short answer

Answer

a.

b.

c.

Step-by-step solution

Aldol reaction

An aldol reaction involves the formation of a $\mathit{\beta }\mathbf{-}$hydroxy carbonyl compound from two carbonyl compounds (aldehyde or ketone).

General aldol reaction

A general aldol reaction is given below:

Aldol reaction

Carbonyl compounds used to prepare the given compounds

Cleaving the carbon-carbon (C-C) bond between the carbon adjacent to the carbonyl compound and the one connected to the hydroxyl group and replacing the alcohol group with a carbonyl group gives the structure of the starting materials used.

a.

Cleavage of C-C bond in a.

The starting materials required are cyclohexanone and 2-methyl propanal.

b.

Cleavage of C-C bond in b.

The starting materials required are phenylacetaldehyde and ketone.

c.

Cleavage of C-C bond in c.

The starting materials required are 4-heptanone and benzaldehyde.