Visible-Light-Induced [4+1] Cyclization-Aromatization of Acylsilanes and ,-Unsaturated Ketones

Herein we report the first [4+1] cyclization-aromatization reaction of acylsilanes and alpha,beta-unsaturated ketones. The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any catalyst or additive, affording a variety of furans with broad substrate scope and good functional-group tolerance. The synthetic utility of the method was demonstrated by various downstream transformations of the otherwise difficult-to-access sulfone-containing silyl furans. The mechanism study reveals that 1,4-diketones are not likely to be the intermediates of the reaction. [GRAPHICS] .