Photocatalytic Silylation of Aryl Alkynoates: Synthesis of Silylated Coumarins

Abstract

Herein, we report the photocatalytic synthesis of 3-silyl coumarins using hydrosilanes as the silyl radical source with aryl alkynoates. Readily prepared N-aminopyridinium salts act as hydrogen atom transfer reagents for generating silyl radicals under photoredox catalysis. The reaction proceeds through a silyl radical addition to alkyne followed by radical cascade cyclization/migration with subsequent oxidation and aromatization to give the desired 3-silyl coumarins in 34–89% yield. © 2024 Wiley-VCH GmbH.