Asymmetric synthesis of .alpha.-alkyl-.alpha. amino acids from chromium-carbene-complex-derived .beta.-lactams
作者:Pierre Jean Colson、Louis S. Hegedus
DOI:10.1021/jo00074a016
日期:1993.10
Optically active bicyclic beta-lactam 3 was synthesized by photolysis of optically active oxazolidine carbene chromium complex 1 with oxazine 2. Conversion of the oxazolidine to the oxazolidinone gave a bicyclic beta-lactam readily alpha-alkylated. Cleavage of the alkylated beta-lactam gave optically active ester aldehyde 7, which was converted to a number of optically active alpha-alkyl-alpha-amino acids. These include (R)-alpha-methylserine, (S)-alpha-methylglutamic acid, (S)-alpha-methylornithine, (S)-vinylalanine, (S)-ethynylalanine, and (S)-2-methyl-2,3-diaminopropionic acid.