Formic Acid → Ethyl 2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetate

Participants

Reaction Conditions

Reaction Steps

A mixture of acetic anhydride (6.1 g) and formic acid (2.8 g) was stirred for 2 hours at 50° C. The resulting mixture was cooled and ethyl 2-methoxyimino-2-(2-amino-1,3-thiazol-4-yl)acetate (syn isomer) (4.6 g) was added thereto at 15° C. After the mixture was stirred for 3.5 hours at ambient temperature, cooled water (100 ml) was added thereto. The resulting mixture was extracted with ethyl acetate (200 ml). The extract was washed with water and then with a saturated aqueous solution of sodium bicarbonate until the washing was changed to weakly alkaline solution. The extract was further washed with a saturated aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off and the residue was washed with diisopropyl ether, collected by filtration and dried to give ethyl 2-methoxyimino-2-(2-formamido-1,3-thiazol-4-yl)acetate (syn isomer) (4.22 g), mp 122° to 124° C. (dec.).

Provenance & Evidence