Carboxylic acids and esters are not easily reduced by catalytic hydrogenation or by NaBH4.
However, relatively more reactive and an expensive LiAlH4 is used to convert carboxylic acids and esters to primary alcohols.
When acetic acid is reduced in the presence of LiAlH4 and followed by their acid hydrolysis, ethyl alcohol is obtained.
When ethyl acetate is reduced in the presence of LiAlH4 and followed by their acid hydrolysis. n-propyl alcohol and ethyl alcohol is obtained.
[Since LiAlH4 is an expensive reagent. commercially acids are reduced to alcohol by converting them to esters, followed by their reduction. (catalytic hydrogenation)
