Direct asymmetric aldol addition–isomerization of α,β-unsaturated γ-butyrolactam with aryl α-ketoesters: synthesis of MBH-type products

Abstract

A highly efficient direct asymmetric aldol addition–isomerization reaction at the α-position of α,β-unsaturated γ-butyrolactam and aryl α-ketoesters by using a bifunctional thiourea catalyst was achieved. Morita–Baylis–Hillman type adducts containing a quaternary stereocenter can be obtained in high yields and with excellent enantioselectivities (up to 99% ee).