Synthesis of Trifluoromethylated Tetrasubstituted Allenes via Palladium-Catalyzed Carbene Transfer Reaction
Chao Pei, Zhen Yang, René M. Koenigs
Abstract
Herein, we report on the palladium-catalyzed synthesis of trifluoromethylated, tetrasubstituted allenes from vinyl bromides and trifluoromethylated diazoalkanes in good to excellent yield. This reaction proceeds via oxidative addition of a Pd(0) complex with vinyl bromide. Subsequent base-promoted reductive elimination generates the allene. This methodology provides an efficient strategy even on gram scale to valuable trifluoromethylated, tetrasubstituted allenes under mild reaction conditions. The allene products can be used in acid catalyzed cyclization reactions to give trifluoromethylated indene products.
Topics & Concepts
ChemistryAlleneCatalysisCarbeneYield (engineering)PalladiumIndeneTrifluoromethylCombinatorial chemistryVinyl bromideOrganic chemistryOxidative additionMedicinal chemistryMetallurgyMaterials scienceAlkylCyclopropane Reaction MechanismsFluorine in Organic ChemistryCatalytic C–H Functionalization Methods