Asymmetric Epoxidation of Alkylidenemalononitriles: Key Step for One-Pot Approach to Enantioenriched 3-Substituted Piperazin-2-ones

The first enantioselective epoxidation of readily available alkylidenemalononitriles has been developed by using a multifunctional cinchona derived thiourea as the organocatalyst and cumyl hydroperoxide as the oxidant. A new simple one-pot asymmetric epoxidation/SN2 ring-opening reaction with 1,2-diamines leading to important enantioenriched heterocycles, i.e. 3-substituted piperazin-2-ones, has been established