Cesium carbonate → HCID 56656122, compound

Participants

Reaction Steps

A solution of Cesium carbonate (3.66 g, 11.2 mmol, 3.0 eq) in Water (1 ml) was charged with a solution of 5-bromo-1-(2,2-dimethylpropyl)-3-methyl-1,3-dihydro-2H-benzimidazol-2-one (1-5, 1.37 g, 3.74 mmol) dissolved in anhydrous THF (19 ml). 3-Hydroxyphenyl boronic acid was introduced and the solution was deoxygenated. The 1,1′-Bis(diphenylphosphino) ferrocene-palladium(II)dichloride dichloromethane complex (153 mg, 0.19 mmol, 0.05 eq) was introduced and the mixture was irradiated in a microwave at 125 deg C. for 15 min. LC/MS analysis showed ˜50% conversion, so more of each reagent was added and the reaction was irradiated again at 120 deg C. for 30 min. The completed reaction was partitioned between EtOAc (2×25 ml) and saturated aqueous NaHCO3 (25 ml), and the combined organic layers were dried over Na2SO4 and concentrated. The crude product was purified via flash column chromatography (SiO2: 100% Hex to 60:40 EtOAc/Hex), affording 1-(2,2-dimethylpropyl)-5-(3-hydroxyphenyl)-3-methyl-1,3-dihydro-2H-benzimidazol-2-one (1479) as a pink-orange solid. 1H NMR (500 MHz, CDCl3) δ 7.34-7.29 (m, 2H), 7.21-7.15 (m, 2H), 7.11-7.06 (m, 2H), 6.81 (d, 1H, J=5.4 Hz), 3.68 (s, 2H), 3.47 (s, 3H), 1.07 (s, 9H). LRMS m/z: Calc'd for C19H22N2O2 (M+H) 311.4, found 311.1.

Provenance & Evidence