Organocatalytic Enantioselective Amination of Morita-Baylis-Hillman Carbonates with Masked Ammonia: A Facile Method for the Synthesis of Unprotected α-Methylene-β-Amino Esters
Amination under the mask: The asymmetric allylicamination of MBH carbonates was achieved with masked ammonia (benzophenone imine) under the catalysis of modified cinchonaalkaloids to give good yields with excellent enantioselectivities (up to 99 % ee) for a wide range of MBH carbonates (see scheme).