title: Stereoselective Synthesis of Trisubstituted Alkenes through Sequential Iron-Catalyzed Reductive anti-Carbozincation of Terminal Alkynes and Base-Metal-Catalyzed Negishi Cross-Coupling.
abstract: The stereoselective synthesis of trisubstituted alkenes is challenging. Here, we show that an iron-catalyzed anti-selective carbozincation of terminal alkynes can be combined with a base-metal-catalyzed cross-coupling to prepare trisubstituted alkenes in a one-pot reaction and with high regio- and stereocontrol. Cu-, Ni-, and Co-based catalytic systems are developed for the coupling of sp-, sp(2) -, and sp(3) -hybridized carbon electrophiles, respectively. The method encompasses a large substrate scope, as various alkynyl, aryl, alkenyl, acyl, and alkyl halides are suitable coupling partners. Compared with conventional carbometalation reactions of alkynes, the current method avoids pre-made organometallic reagents and has a distinct stereoselectivity.
authors.affiliation: Laboratory of Inorganic Synthesis and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISCI-LSCI, BCH 3305, 1015 Lausanne (Switzerland).
authors.forename: Chi Wai
authors.initials: CW
authors.lastname: Cheung
authors.affiliation: Laboratory of Inorganic Synthesis and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISCI-LSCI, BCH 3305, 1015 Lausanne (Switzerland). xile.hu@epfl.ch.
authors.forename: Xile
authors.initials: X
authors.lastname: Hu
keywords: carbozincation; catalysis; cross-coupling; iron; olefin synthesis; stereoselective