Chitosan-supported cinchona urea: Sustainable organocatalyst for asymmetric Michael reaction

A novel chitosan-supported cinchona urea heterogeneous catalyst was developed for asymmetric reaction. The catalytic activity of the chitosan-supported organocatalyst was examined in the asymmetric Michael addition reaction to give chiral adducts in good yields with excellent enantioselectivities (up to 99% ee). The insolubility of the chitosan-supported cinchona urea catalyst facilitated catalyst recovery. The catalyst was easily separated and reused without any loss in catalytic activity.