Metal-Free Catalytic Reduction of Amides: Recent Progress

Amines are one of the most important functional groups in organic synthesis, particularly in scaffolds constituting the active ingredients of natural products, pharmaceutical molecules, and agrochemicals. Among various transformations to access amines, amide reduction has been considered as the most facile and efficient strategy, but it is also one of the most problematic, often requiring the use of highly reactive stoichiometric reductants, such as lithium aluminum hydride, as well as rare transition metal catalysts, or both, and harsh reaction conditions. This review covers recent advances in the catalytic reduction of amides to amines without the need for metal catalysts, thus overcoming such problems.