Reagent for the Chemoselective Reduction of Carboxylic Acids to Aldehydes

Organic Letters 2025, 27, 44, 12391–12395

No over reduction to primary alcohols detected, works on aromatic and aliphatic aldehydes, no epimerization of alpha-chiral centers, no inert atmosphere or anhydrous conditions, good to excellent yields with a good substrate scope. Dump and stir at RT, filter, rotovap, column.

It also works on esters when they use LiOH instead of LiCO3 (via in situ hydrolysis of the ester to form the carboxylate which is reduced).

Maybe I'm missing something but this looks super convenient and useful. The reagent is not widely or cheaply commercially available yet but is synthesized in 2 steps with no chromatography