Cesium carbonate → HCID 10133843, compound

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3-(3-bromo-4-fluorophenyl)-7-trifluoromethylimidazo[1,2-α]pyrimidine (150 mg, 0.42 mmol) and 3-(5,5-dimethyl-[1,3,2]dioxaborinan-2-yl)-5-methylpyridine in 1,4-dioxane (5 ml) was added a solution of caesium carbonate (340 mg, 1.04 mmol) in water (0.5 ml). The reaction was degassed with nitrogen and tetrakis(triphenylphosphine)palladium(0) (48 mg, 0.04 mmol) was added and the mixture heated at 70° C. for 1 h. The solvent was evaporated in vacuo and the residue was partitioned between dichloromethane and water. The aqueous phase was re-extracted with dichloromethane and the combined organic layers dried over anhydrous magnesium sulphate, filtered and evaporated. The residue was purified using a short silica gel column eluting with 2% diethyl ether in dichloromethane followed by 15% diethyl ether in dichloromethane to give a yellow solid. This was purified further by loading as a solution in methanol onto a cartridge of strong cation-exchange resin, eluting with methanol then with 2M ammonia in methanol. The basic fractions were concentrated in vacuo to give a dark cream solid. The solid was triturated with diethyl ether to give 3-[4-fluoro-3-(5-methylpyridin-3-yl)phenyl]-7-trifluoromethylimidazo[1,2-α]pyrimidine as a cream solid (55 mg, 35%): δH (360 MHz, d6-DMSO) 2.39 (3H, s), 7.51 (1H, d, J 7), 7.60 (1H, dd, J 11 and 9), 7.85 (1H, ddd, J 9, 5 and 2), 7.91-7.94 (1H, m), 8.00 (1H, dd, J 7 and 2), 8.33 (1H, s), 8.49 (2H, d, J 2), 8.68-8.71 (1H, m), 9.36 (1H, d, J 7); m/z (ES+) 373 (M++H).

Provenance & Evidence