Enantioselective Functionalization of Difluorocyclopropenes Catalyzed by Chiral Copper Complexes: Proposal for Chiral <i>gem</i>-Dimethyl and <i>tert</i>-Butyl Analogues
Keisuke Sekine, Aina Ushiyama, Yu Endo, Koichi Mikami
Abstract
The highly enantioselective copper/chiral phosphine-catalyzed hydro-, bora-, and carbo-metalations of difluorocyclopropenes with PHMS [H-Si], H-BPin, (BPin)2, and (CH3)2Zn [Zn-Me] are shown to regiodivergently afford highly enantioenriched and functionalized difluorocyclopropanes. These examples can be viewed as the first successful syntheses of “chiral” gem-dimethyl and tert-butyl analogues.
Topics & Concepts
Enantioselective synthesisCopperPhosphineCatalysisSurface modificationChemistryCombinatorial chemistryStereochemistryOrganic chemistryPhysical chemistryFluorine in Organic ChemistryCyclopropane Reaction MechanismsAsymmetric Synthesis and Catalysis