Carboxylic acids and esters are reduced to alcohols with lithium aluminum hydride. Milder reducers such as sodium borohydride are unable to reduce these compounds.

synthesis-alcohols-reduction-acids

Ethanoic acid [1] is transformed by reduction with lithium aluminum hydride in ethanol [2].

synthesis-alcohols-reduction-esters
Methyl benzoate [1] is converted to benzyl alcohol [2] by reduction with lithium aluminum hydride.