Ethyl chloroformate → ethyl 6-chloro-3-oxo-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate

Participants

Reaction Steps

To a solution of 6-chloro-1H-pyrazolo[4,3-c]pyridin-3(2H)-one (2.64 g, 15.57 mmol) in pyridine (10 mL) and water (14 mL) was added ethyl chloroformate (3.38 g, 31.1 mmol) drop-wise at 0° C. The reaction was removed from the ice bath and was stirred at room temperature overnight. The reaction mixture was filtered and the solid rinsed with water to afford ethyl 6-chloro-3-oxo-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate, which was carried onto the next step without further purification. MS ESI calc'd. for C9H8ClN3O3 [M+1]+242. found 242.

Provenance & Evidence