Photoreaction of halomethyl substituted benzocyclic ketones with amines: radical cyclization and ring expansion reactions promoted through photoinduced electron transfer processes

Abstract

Photoreaction of ethyl 2-bromomethyl-1-oxo-1,2,3,4- tetrahydronaphthalene-2-carboxylate 1a or other related compounds 1b–d with Me₃SiCH₂NEt₂ in aqueous MeCN afforded ethyl 5-oxo-6,7,8,9-tetrahydrobenzocycloheptene-7-carboxylate 2a or corresponding ring expansion products 2a–d respectively.