Transition-Metal-Free Ring-Opening Silylation of Indoles and Benzofurans with (Diphenyl-tert-butylsilyl) lithium

摘要

A practical method is presented for ring opening various indoles and benzofurans with concomitant stereoselective silylation using readily generated (diphenyl-tert-butylsilyl) lithium to afford ortho-beta-silylvinylanilines or -phenols. Dearomatization of the heteroarene core proceeds in the absence of any transition-metal catalyst through addition of a silyl anion and a subsequent stereoselective beta-elimination. DFT calculations provide insight into the mechanism. Functionalizing C-X bond cleavage of heteroarenes is rare and generally requires transition-metal catalysts.