2-Aminothiazole → Ethyl 6-methylimidazo[2,1-b]thiazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 1,3-thiazol-2-amine (10 g, 100 mmol), ethyl 2-chloro-3-oxobutanoate (16 g, 100 mmol) and ethanol (100 mL) was stirred at 80° C. for 1 day. The reaction mixture was concentrated under reduced pressure, saturated aqueous sodium bicarbonate solution was added to the obtained residue, and the mixture was extracted with ethyl acetate. The collected organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The insoluble material was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (ethyl acetate/hexane=20/80→50/50) and washed with diisopropyl ether to give the title compound (5.5 g, 26%) as a colorless solid.

Provenance & Evidence