Asymmetric synthesis of 3,5-bis(isopropyloxy)-4-methoxyphenyl glycine by way of a diastereoselective Strecker reaction and an Evans electrophilic amination reaction

Two short syntheses of D-N-Boc-3,5-bis(isopropyloxy)-4-methoxyphenylglycine, a central unit of vancomycin type antibiotics, have been developed. A diastereoselective Strecker amination reaction using (S)-phenylglycinol as a chiral inducer was the key step in the first synthesis, while Evans' electrophilic azidation technol. was employed for introducing both the amino function and the chirality in the second strategy. [on SciFinder (R)]