Quinine catalysed asymmetric Michael additions in a sustainable solvent

Abstract

Diethyl carbonate is shown to be a suitable, sustainable solvent in which to carry out quinine catalysed asymmetric Michael additions of malononitriles to enones. Both malonitrile and α-substituted malononitriles can be used as substrate and the results suggest that π–π stacking interactions between the (hetero)aromatic rings of the catalyst and substrates are important in determining the degree of asymmetric induction.