Asymmetric synthesis of functionalized cyclohexanes bearing five stereocenters via a one-pot organocatalytic Michael-Michael-1,2-addition sequence

摘要

A highly stereoselective one-pot procedure involving an enantio-selective Michael addition promoted by low loading of an amino-squaramide catalyst followed by an achiral base catalyzed domino Michael-Knoevenagel-type 1,2-addition sequence provides efficient access to fully substituted cydohexanes bearing five contiguous stereogenic centers in good yields (68-86%) and excellent stereo-selectivities (＞30:1 dr and 96-99% ee).