Question 13.2: Predicting the Structure of a Reactant, Given the Product Wh...
Predicting the Structure of a Reactant, Given the Product
What carbonyl compounds would you reduce to obtain the following alcohols?
Strategy
Identify the target alcohol as primary, secondary, or tertiary. A primary alcohol can be prepared by reduction of an aldehyde, an ester, or a carboxylic acid; a secondary alcohol can be prepared by reduction of a ketone; and a tertiary alcohol can’t be prepared by reduction.
(a) The target molecule is a secondary alcohol, which can be prepared only by reduction of a ketone. Either NaBH_{4} or LiAlH_{4} can be used.
(b) The target molecule is a primary alcohol, which can be prepared by reduction of an aldehyde, an ester, or a carboxylic acid. LiAlH_{4} rather than NaBH_{4} is needed for the ester and carboxylic acid reductions.
