Solvent free, fast and asymmetric Michael additions of ketones to nitroolefins using chiral pyrrolidine-pyridone conjugate bases as organocatalysts

New chiral organocatalysts are envisaged based on a pyrrolidine-pyridone conjugate and synthesized from commercially available proline employing standard protocols. These catalysts were found to be useful for asymmetric Michael additions of ketones to nitroolefins to afford the desired products in very good yields (up to 98%) with excellent diastereo- and enantioselectivities (>97:3 syn/anti and up to 98% ee) in very short reaction time compared with the existing reports. (C) 2017 Elsevier Ltd. All rights reserved.