Pyrrolidine-Based Organocatalysts for Enantioselective Michael Addition of Cyclohexanone to trans-β-Nitrostyrene

A series of readily prepared bifunctional catalysts promote the Michael addition of cyclohexanone to trans-?-nitrostyrene with excellent asymmetric induction. The enantioselection (up to 97%) and diastereoselection (up to 95:5) is comparable to other pyrrolidine­-thiourea organocatalysts recently reported, however, reaction times are often shorter