Cesium carbonate → HCID 89700178, compound

Participants

Reaction Steps

Under argon, 12.3 g (35.2 mmol) of the compound of Example 1A, 9.9 g (45.8 mmol) of 2-bromo-4-nitrotoluene, 0.79 g (3.52 mmol) of palladium(II) acetate, 22.9 g (70.4 mmol) of caesium carbonate and 2.04 g (3.52 mmol) of xantphos [4,5-bis(diphenylphosphino)-9,9-dimethylxanthene] in 170 ml of 1,4-dioxane were heated at reflux for 4 h. After cooling to RT, the mixture was filtered through kieselguhr and the filtrate was concentrated on a rotary evaporator. The residue was taken up in ethyl acetate and the mixture was washed with semiconcentrated sodium bicarbonate solution and then with concentrated sodium chloride solution. The organic phase was dried over anhydrous sodium sulphate and concentrated. The crude product was purified chromatographically on silica gel (mobile phase gradient dichloromethane/ethyl acetate 2:1→1:3). This gave 15.9 g (92% of theory) of the title compound.

Provenance & Evidence