Triethylamine → 5-(3,4-Dichloro-phenyl)-oxazole-4-carboxylic acid methyl ester

Participants

Reaction Steps

A solution of methyl isocyanoacetate (5.0 g, 50.0 mmol), 3,4-dichlorobenzoyl chloride (10.6 g, 50.0 mmol), and Et3N (20.9 mL, 150 mmol) was stirred in THF (20 mL) for 48 h at rt. The solution was concentrated, diluted with EtOAc, washed with water, dried (MgSO4), and concentrated to afford a solid. The solid was washed with hexanes and collected by filtration to provide 8.7 g (64%) of the desired product. HPLC: RT=9.68 min. MS (ESI+): mass calcd. for C11H7Cl2NO3, 270.98; m/z found, 272/274 [M+H]+. 1H NMR (400 MHz, CDCl3): 8.29 (d, J=2.1, 1H), 8.03 (dd, J=8.5, 2.1, 1H), 7.94 (s, 1H), 7.56 (d, J=8.5, 1H), 3.98 (s, 3H).

Provenance & Evidence