title: Stereoselectivity in the Michael Addition Reaction of Dialkylcuprates to the 2-Cyclohexenones with C-4 Ester Substituents.
abstract: Stereoselectivity in the Michael addition of (Me2C=CH)2CuMgBr and (Me2C=CH)2CuLi to 3-alkyl/H-4-[(tert-butoxycarbonyl)alkyl]-2-cyclohexenone was studied. (Me2C=CH)2CuMgBr showed stereoselectivity in all cases (3-H, Me: anti; 3-n-Bu: syn). This stereoselectivity disappeared in the reaction of (Me2C=CH)2CuLi with 4-[(tert-butoxycarbonyl)methyl]-3-butyl-2-cyclohexenone. However, the stereoselectivity was recovered by elongating the 4-alkyl chain of 2-cyclohexenone to show the same selectivity as that of (Me2C=CH)2CuMgBr.
authors.affiliation: a College of Agriculture, Ehime University.
authors.forename: S
authors.initials: S
authors.lastname: Yamauchi
authors.affiliation: a College of Agriculture, Ehime University.
authors.forename: M
authors.initials: M
authors.lastname: Kadoya
authors.affiliation: a College of Agriculture, Ehime University.
authors.forename: M
authors.initials: M
authors.lastname: Kitagawa
authors.affiliation: a College of Agriculture, Ehime University.
authors.forename: Y
authors.initials: Y
authors.lastname: Kinoshita
keywords: Michael addition