Chemoselective Photoredox Synthesis of Unprotected Primary Amines Using Ammonia.

Unprotected α-amino carbon radicals are produced as novel intermediates via a transformation that merges acid-promoted N-H imine generation and chemoselective photocatalytic single-electron reduction. Coupling ammonia and aldehydes/ketones allows the generation of primary amines under mild conditions without the need for protecting groups. The key intermediate can be efficiently transformed into primary (di)amines by a formal dimerization, reductive amination via hydrogen atom transfer, and arylation through radical-radical coupling.