Samarium triflate-catalyzed dimerization of vinylarenes

Abstract

We report the preparation of substituted indanes and their dimeric isomers via the samarium triflatemediated [Sm(OTf)3, 10 mol%] self-dimerization of vinylarenes in MeNO2 at 25 o C for 10 h. The diverse products were obtained in moderate to high yields. The synthesis involves a (3+2) annulation via the formation of carbon-carbon bonds. Plausible mechanisms are proposed and discussed. The investigation of various rare metal triflates catalyst loadings, reaction conditions, and substrate scope led to an operationally easy one-pot Friedel-Crafts reaction protocol.

Samarium(III) Triflate in Organic Synthesis: a Mild and Efficient Catalyst

“…[39] In another study, Chang et al reported the synthesis of substituted indanes and dimeric isomers in the presence of the Sm(OTf) 3 (10 mol%) involving an [3 + 2] annulation in 2019 (Scheme 5). [40] Vinylarenes 6 in nitromethane delivered indanes 7 and their dimeric isomers 8 at 25 °C for 10 h in moderate yields through the CÀ C bond constructing protocol.…”