反应详情

General procedure B using (S)-p-tol-BINAP and 3-(3-oxo-cyclopent-1-enyl)-propionic acid methyl ester (0.084 g, 0.5 mmol) gave, after 24 h at 0° C. and flash chromatography (4:1, then 2:1 hexane:ethyl acetate), the title compound as a clear oil (0.075 g, 88% yield). Spectroscopic data were consistent with previously reported data for this compound.15 [α]D25° C.−112° (c 1.3, CHCl3). Conversion of the title compound to the corresponding benzyl ester followed by chiral HPLC analysis (Chiracel OD column) indicated that the title compound was obtained in 91% ee.

1. customgave, after 24 h at 0° C.