B(C6F5)3-Catalyzed Reductive Deoxygenation of Isatins for Indole Synthesis

Abstract

An efficient method for reductive deoxygenation of isatin derivatives using catalyst B(C₆F₅)₃ and methylphenylsilane is described. This reaction proceeds rapidly under mild conditions, and the protocol provides a broad substrate scope. Notably, while general synthetic methods utilizing a combination of B(C₆F₅)₃ and hydrosilanes smoothly reduce indoles to generate indolines, the present strategy represents the first reductive deoxygenation reaction for the formation of indoles without further reduction.