Chemical resolution of enantiomers of 3,4-dihydropyrimidin-2(1H)-ones using chiral auxiliary approach

Inherently racemic DHPMs have been resolved using chemical resolution methodology by appending enantiopure chiral auxiliary at N-1 or N-3 position of the DHPMs, leading to the formation of both diastereomers, which were separated chromatographically to obtain both enantiomers (ee upto 99.9%) of DHPMs, after removal of the auxiliary. Absolute configuration of the enantiomers has been assigned.