Synthesis of Optically Pure (S,E)-2-Amino-5-arylpent-4-enoic Acids by Heck Reactions of Nickel Complexes

Starting from commercially available building blocks a variety of enantiomerically pure ( S )-2-amino-4-enoic acids has been synthesized by the Heck reaction using Ni-( S )-BPB {Nickel- N -[( S )-benzylprolyl]aminobenzophenone} as a chiral auxiliary. The reactions proceeded in very good yields and with high E -selectivity.