Visible-Light-Mediated Radical Hydroalkylative Cyclization of 1,6-Enynes.

A radical hydroalkylative cyclization approach accessing various alkenyl heterocyclic compounds was developed using dimethyl malonate and 1,6-enynes in the presence of visible-light photoredox catalysis. The use of Ir(dtbbpy)(ppy) 2 PF 6 as a photosensitizer enables carbon atom radical formation and initiates the cascade cyclization reaction under mild conditions.