Cesium carbonate → 2-[(5-{{[4-(tert-butyl)phenyl]sulfonyl}[(2-methoxyethoxy)methyl]amino}-1-methyl-4-phenyl-1H-pyrazol-3-yl)oxy]ethyl acetate

Participants

Reaction Steps

2-[(5-{{[4-(tert-Butyl)phenyl]sulfonyl}[(2-methoxyethoxy)methyl]amino}-4-iodo-1-methyl-1H-pyrazol-3-yl)oxy]ethyl acetate (Preparation 14) (1.95 g), benzeneboronic acid (0.78 g) and cesium carbonate (5.26 g) were suspended in 1,4-dioxane (50 ml) and water (5 ml). The mixture was degassed (vacuum and nitrogen atmosphere×5) and then tetrakis(triphenylphosphine)palladium(0) (50 mg) was added and the mixture degassed again. The mixture was heated at reflux for 2 hours and cooled to room temperature overnight. The reaction was quenched with saturated aqueous sodium bicarbonate solution and extracted with ethyl acetate (20 ml×3). The combined organics were washed with saturated aqueous sodium bicarbonate solution, dried with magnesium sulfate, filtered and concentrated under reduced pressure. Chromatography on silica eluting with a gradient elution of ethyl acetate:hexane (1:2 to 2:1) yielded the desired product as an off white solid (1.112 g).

Provenance & Evidence