Potassium Carbonate → Ethyl 1-(3-methyl-2-pyridyl)-4-formyl-pyrazole-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 1-(3-chloro-2-pyridyl)-4-formyl-pyrazole-3-carboxylate (1.0 g, 3.5 mmol), trimethylboroxine (0.44 g, 3.50 mmol) and potassium carbonate (1.4 g, 10.1 mmol) in dioxane (18 mL) and water (2 mL) is degassed with nitrogen gas for 10 min and then palladium triphenylphosphine (0.40 g, 0.3 mmol) is added and stirred at 110° C. for 16 h. After completion, the reaction mixture is partitioned between dichloromethane (50 mL) and water (25 mL). The aqueous layer is extracted with dichloromethane (2×25 mL) and the combined organic extracts are dried over sodium sulfate and concentrated in vacuo. The crude mixture is purified by column chromatography over silica gel eluting with hexane/ethyl acetate (70:30) to yield 0.12 g (13%) of the title compound. MS (m/z): 260 (M+1).

Provenance & Evidence