The Intramolecular Rauhut−Currier Reaction between Nitroalkenes and Acrylates: An Approach to 3‐Methylene‐3,4‐Dihydrocoumarin Scaffold

Abstract

The intramolecular Rauhut−Currier reaction between nitroalkene and acrylate has been successfully carried out. The reaction proceeds in the presence of a sulfinamide based bifunctional phosphine in dichloromethane to provide the biologically relevant 3‐methylene‐3,4‐dihydrocoumarin in acceptable yields. Unlike with other nitroalkenes participated cross R−C reactions, in this reaction, nitroalkenes work as electrophiles rather than nucleophiles. The nature of the substituent plays an important role on the chemoselectivity of this reaction. Normal Rauhut−Currier reaction products were obtained for substrates with electron‐donating substituent on the benzene ring, whereas isomerized coumarin products were obtained for those bearing halogen substituent.