Phosphorus oxychloride → Ethyl 2-(2-amino-1,3-thiazol-4-yl)glyoxylate hydrochloride

Participants

Reaction Steps

To a suspension of ethyl 2-(2-formylamino-1,3-thiazol-4-yl)glyoxylate, which can be represented as ethyl 2-(2-formylimino-2,3-dihydro-1,3-thiazol-4-yl)glyoxylate, (31.3 g.) in ethanol (600 ml.) was dropwise added phosphorus oxychloride (41.9 g.) under ice-cooling and stirring, and the mixture was stirred for 30 minutes at 50° C. After the reaction, the solvent was distilled off. The residue was washed with diethyl ether and then dried to give ethyl 2-(2-amino-1,3-thiazol-4-yl)glyoxylate hydrochloride, which can be represented as ethyl 2-(2-imino-2,3-dihydro-1,3-thiazol-4-yl)glyoxylate hydrochloride, in quantitative yield, mp. 263° to 264° C. (dec.).

Provenance & Evidence