Potassium Carbonate → HCID 59333308, compound

Participants

Reaction Steps

A solution of 3-(8-bromo-7-trifluoromethyl-imidazo[1,2-a]quinoxalin-4-ylamino)-propan-1-ol prepared as in example 52 (1 g; 2.57 mmol; 1 eq), 1,1′bis(diphenylphosphino) ferrocene)palladium dichloride. Dichloromethane complex (210 mg; 0.257 mmol; 0.1 eq), vinylboronic acid pinacol ester 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane (700 μl; 4.1 mmol; 1.6 eq), potassium carbonate (1.42 g; 10.28 mmol; 4 eq) in acetonitrile (12 ml) and water (4 ml) is stirred 24 h at 65° C. under argon. The conversion being slow the reaction mixture is stirred for 3 additional days at 65° C. under argon with daily addition of 1,1′bis(diphenylphosphino) ferrocene)palladium dichloride. dichloromethane complex (105 mg; 0.129 mmol; 0.05 additional eq) and vinylboronic acid pinacol ester 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane (500 μl; 2.9 mmol; 1.1 additional eq). Concentration, partition (ethyl acetate/water), extraction of the aqueous phase (ethyl acetate), reunion of the organic phases, drying (magnesium sulphate) and purification by flash chromatography on silica gel (gradient of methanol 0 to 20% in dichloromethane) followed by trituration in methanol afforded the title compound (118 mg; 0.351 mmol; 14%) as a pale yellow powder.

Provenance & Evidence