Ethyl 3-(N,N-dimethylamino)acrylate → Ethyl 3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylate

Participants

Reaction Steps

Aluminum chloride (298 mg) was added portionwise to a solution of 2-phenylpyrazolo[1,5-a]pyridine (145 mg) and ethyl 3-dimethylaminoacrylate (316 mg) in methylene chloride (2 ml) at 5° to 6° C. After being stirred at room temperature overnight, the reaction mixture was poured onto water (50 ml), neutralized with saturated aqueous sodium bicarbonate solution, and extracted with chloroform (50 ml×2). The extracts were washed with saturated sodium chloride aqueous solution (20 ml), dried over magnesium sulfate, and evaporated in vacuo. The residue was chromatographed on silica gel with a mixture of chloroform and n-hexane (1:1) as an eluent. The fractions containing the objective compound were combined and evaporated in vacuo to give ethyl 3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylate (trans isomer) (189.4 mg).

Provenance & Evidence