Potassium Phosphate, Tribasic → HCID 86692440, compound

Participants

Reaction Conditions

Reaction Steps

Vinylboronic acid pinacol ester (1.37 ml), tripotassium phosphate (3.85 g) and 1,1′-bis(diphenylphosphino)ferrocene-palladium (II) dichloride dichloromethane complex (301 mg) were added to a solution of 1-(5-bromo-3-chloropyridin-2-yl)-5-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (2.52 g) described in Reference Example 44(2) in N,N-dimethylformamide (36 ml), and the mixture was stirred at 100° C. for seven hours. The reaction solution was cooled to room temperature, diluted with water, filtered through Celite and the filtrate was extracted with ethyl acetate three times. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate and concentrated. The resulting residue was purified with silica gel column chromatography (n-hexane/ethyl acetate) to give 1-(3-chloro-5-vinylpyridin-2-yl)-5-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (1.67 g).

Provenance & Evidence