Enantioselective Mannich reaction of a highly reactive Horner-Wadsworth-Emmons reagent with imines catalyzed by a bifunctional thiourea

N-acyl pyrrole phosphonates were identified as a class of highly reactive HWE reagents. The asymmetric addition of the present HWE reagents to N-carbamoyl imines generated in situ was achieved. The corresponding Mannich adducts can be further transformed to aza-MBH type products in good to excellent enantioselectivities.