Polydentate hydrazones as multitasking catalysts in visible-light-induced coupling reactions of amines

A Cu/hydrazone catalyst has been applied in the coupling reactions of anilines for the synthesis of diarylamines and azobenzenes. The copper complex that is formed in situ plays a double duty by harnessing photon energy as a photocatalyst and then by catalysing organometallic elementary steps as a transition metal catalyst. By the selection of hydrazones and bases, the reaction selectivity of aniline can be tuned between homo-coupling and its cross-coupling with arylboronic acid, exhibiting the great potential of such hydrazones in organic synthesis.

Automated summary

A Cu/hydrazone catalyst has been utilized for coupling reactions of anilines to synthesize diarylamines and azobenzenes. The in situ formation of a copper complex enables the catalyst to function as both a photocatalyst, harnessing photon energy, and a transition metal catalyst, catalyzing organometallic elementary steps. By choosing appropriate hydrazones and bases, the reaction selectivity of aniline can be tuned between homo-coupling and cross-coupling with arylboronic acid, demonstrating the promising applications of hydrazones in organic synthesis.