文摘
An efficient enantioselective synthetic method for (S)-α-alkyl-α,β-diaminopropionic acid is reported. The asymmetric phase-transfer catalytic alkylation of N(1)-Boc-2-phenyl-2-imidazoline-4-carboxylic acid tert -butyl ester in the presence of chiral quaternary ammonium catalyst gave the corresponding alkylated products (93−98% ee) which could be transformed to enantioenriched α-alkyl-α,β-diaminopropionic acids.