Decatungstate-Photocatalyzed Hydroamidomethylation of Azobenzenes with ,-Dimethylamides.

A photocatalytic hydroamidomethylation of azobenzenes with ,-dimethylamides has been developed. Using tetrabutylammonium decatungstate (TBADT) as a photocatalyst, an array of azobenzenes and ,-dimethylamides reacted smoothly under visible light irradiation, affording previously unreported -amidomethyl-,'-diarylhydrazines in generally high yields. Mechanistic studies indicate that the reaction is enabled by TBADT-mediated hydrogen atom transfer (HAT) photocatalysis. This work is fundamentally different from the previously reported reaction of ,-dimethylformamide with azobenzenes.