Visible-Light-Induced Tandem Radical Addition–Cyclization of Alkenyl Aldehydes Leading to Indanones and Related Compounds

Herein we describe a novel, visible light-induced tandem radical addition–cyclization of alkenyl aldehydes with α<i>-</i>bromocarbonyl compounds. A set of cyclic ketones, including indanones, cyclopentenones, 3,4-dihydro­naphthalen-1­(2<i>H</i>)-ones, and chroman-4-ones, are synthesized at room temperature with high efficiency and good functional group compatibility. It represents the first report on the catalytic 1,2-acylalkylation of unactivated alkenes