Enantioselective Mukaiyama-Michael Reaction of Cyclic α-Alkylidene β-Keto Phosphine Oxide and Phosphonate and Asymmetric Synthesis of (R)-Homosarkomycin.

The asymmetric Mukaiyama-Michael reaction of cyclic α-alkylidene β-oxo phosphates and phosphine oxides that proceeds in a highly enantioselective manner is described. It is possible to carry out these reactions using a catalytic amount of a bisoxazoline-Cu(II) complex without decreasing the enantioselectivity, and one of the products has been successfully used for the first enantioselective synthesis of (R)-homosarkomycin.