T. Cynkowski et al., REACTION OF N-BENZOYL AMINO-ACIDS WITH OXALYL CHLORIDE - A FACILE ROUTE TO 4-SUBSTITUTED 2-PHENYLOXAZOLE-5-CARBOXYLATES, Journal of the Chemical Society, Chemical Communications, (22), 1995, pp. 2335-2336
N-benzoyl amino acids 1a-g react with excess oxalyl chloride at room t
emperature followed by addition of alcohols to afford 4-substituted 2-
phenyloxazole-5-carboxylates 3a-g.