A Palladium-Catalyzed Dehydrogenative Diamination of Terminal Olefins

摘要

Metal-mediated and -catalyzed diamination of olefins provides an effective approach to vicinal diamines, which are very important functional moieties contained in various biologically active compounds and are widely used as chiral-control elements in asymmetric synthesis. Recently, we reported that various dienes and trienes can be regio- and stereoselec-tively diaminated using di-tert-butyldiaziridinone (2) as the nitrogen source and palladium(O) or copper(I) as the catalyst. When readily available terminal olefins were treated with 2 and [Pd(PPh3)4], the diamination occurred regio- and diastereoselectively at the allylic and homoallylic carbon centers to form 3 (Scheme 1). This reaction is likely to proceed via a diene species which is formed in situ. However, when N,N-di-tert-butylthiadiaziridine 1,1-dioxide is used as the nitrogen source along with the Pd catalyst, then terminal olefins are regioselectively diaminated at the terminal carbon position to form 5 via a different reaction mechanism to that already reported (Scheme 2). Herein, we report our preliminary results on this subject.