Carbene-Catalyzed Reductive Coupling of Nitrobenzyl Bromide and Nitroalkene via the Single-Electron-Transfer (SET) Process and Formal 1,4-Addition.

A carbene-catalyzed reductive 1,4-addition of nitrobenzyl bromides to nitroalkenes is disclosed. The reaction proceeds via a carbene-enabled single-electron-transfer process that generates radicals as key intermediates. The present study expands the potentials of carbene catalysis and offers unusual transformations for common substrates in organic synthesis.