pyrrolidine gave a dipeptide-connected amidomonophosphane ligand for the highly efficient, copper-catalyzed asymmetric conjugateadditionreaction of organozinc reagents with cycloalkenones, giving 3-alkylated cycloalkanones in high enantioselectivity of up to 98 % ee. A model that predicts the stereochemistry of the reaction is discussed.
Asymmetric synthesis using enantiomerically pure 2-(p-anisylsulfinyl)-2-cycloalkenones
作者:Gary H. Posner、Leah L. Frye、Martin Hulce
DOI:10.1016/s0040-4020(01)82425-x
日期:1984.1
Conjugateadditions of many organometallic reagents to 2-(p-anisylsulfinyl)-2-cycloalkenones, 2 proceed with much greater diastereoselectivity than additions to the corresponding 2-(p-tolylsulfinyl)-2-cycloalkenones, 7. Complexation of 2 with zinc dibromide followed by addition of various Grignard reagents lead, after reductive removal of the sulfoxide, to 3-substituted cycloalkanones of higher optical