Palladium/Silver-Cocatalyzed Tandem Reactions of Oxabenzonorbornadienes with Substituted Arylacetylenes: A Simple Method for the Preparation of 1,2-Diarylethanones and 1,2-Diarylacetylenes

Abstract

The effective synthesis of 1,2-diarylethanones was achieved using palladium­(II) acetate [Pd­(OAc)₂] and silver triflate (AgOTf) as cocatalysts from various oxabenzonorbornadiene derivatives and substituted arylacetylenes via tandem reactions under mild conditions. Exploration of the oxabenzonorbornadiene substrates showed that the 1,2-diarylacetylenes were obtained from adjacent alkoxy substituted oxabenzonorbornadiene derivatives. Preliminary mechanistic studies indicate that the AgOTf served as an indispensable catalyst, and the mechanism of the tandem reaction was proposed