Carbene catalyzed selective addition of isothioureas to enals for access to sulphur containing 5,6 dihyropyrimidin 4 ones
A carbene catalyzed addition reaction between isothioureas and enals under oxidative conditions is reported. The key steps of our reactions involve the formation of two carbon nitrogen bonds in a highly regio selective manner. A variety of sulphur containing 5,6 dihydropyrimidin 4 ones are obtained with high optical purity.