Cyclopeptoids as Phase‐Transfer Catalysts for the Enantioselective Synthesis of α‐Amino Acids

Abstract

Abstract The first application of cyclopeptoids in asymmetric phase‐transfer catalysis was examined. A small library of nine alternating N ‐substituted‐glycine and proline hexacyclopeptoids was tested in the enantioselective alkylation of N ‐(diphenylmethylene)glycine tert ‐butyl ester. The presence of an N ‐arylmethyl side chain in the catalyst was found to be crucial for the synthesis of α‐amino acids with up to 73 % ee .