title: Highly versatile enantioselective conjugate addition of Grignard reagents to alpha,beta-unsaturated thioesters.
abstract: Herein, we report efficient catalysts for the asymmetric copper-catalyzed conjugate addition of Grignard reagents to alpha,beta-unsaturated thioesters. MeMgBr adds to aromatic alpha,beta-unsaturated thioesters with excellent enantioselectivities and moderate to good yields using Josiphos/CuBr and Tol-BINAP/CuI complexes. The use of bulky Grignard reagents leads to unprecedented enantioselectivities in the 1,4-addition to a broad range of aromatic and aliphatic alpha,beta-unsaturated thioesters using Tol-BINAP/CuI. The highest enantioselectivities reported so far for the addition of Grignard reagents to crowded beta-substituted aliphatic substrates are achieved with Tol-BINAP/CuI.
authors.affiliation: Department of Organic and Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
authors.forename: Beatriz Maciá
authors.initials: BM
authors.lastname: Ruiz
authors.forename: Koen
authors.initials: K
authors.lastname: Geurts
authors.forename: M Angeles
authors.initials: MA
authors.lastname: Fernández-Ibáñez
authors.forename: Bjorn
authors.initials: B
authors.lastname: ter Horst
authors.forename: Adriaan J
authors.initials: AJ
authors.lastname: Minnaard
authors.forename: Ben L
authors.initials: BL
authors.lastname: Feringa
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry*; D007202:Indicators and Reagents / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D004952:Esters; D007202:Indicators and Reagents; D003300:Copper