Potassium Carbonate → 6-(1-Hydroxy-1,3-dihydro-benzo[c][1,2]oxaborol-5-yloxy)-2-isopropoxy-nicotinonitrile

Participants

Reaction Conditions

Reaction Steps

To a mixture of 6-chloro-2-propoxy-nicotinonitrile (0.54 g, 3.0 mmol) and 3H-benzo[c][1,2]oxaborole-1,5-diol (0.40 g, 2.0 mmol) in DMF (10 mL) was added potassium carbonate (0.83 g, 6.0 mmol). The resulting suspension was heated at 95° C. for 48 h. DMF was removed under reduced pressure, the residue was diluted with EtOAc (50 mL), washed with water (10 mL) and brine (2×10 mL), dried over Na2SO4, filtered, and concentrated to give brown oil. Purification was accomplished by reverse phase preparative HPLC using MeOH/H2O (0.1% AcOH) as the eluent to yield the title compound (0.25 g, 26%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 9.25 (s, 1H), 8.24 (d, J=8.2 Hz, 1H), 7.79 (d, J=7.8 Hz, 1H), 7.29 (s, 1 H), 7.17-7.22 (m, 1H), 6.69 (d, J=8.6 Hz, 1H), 4.99 (s, 2H), 4.07 (t, J=6.8 Hz, 2H), 1.65-1.55 (m, 2H), 0.81 (t, J=7.4 Hz, 3H); MS (ES) m/z: 311 (M+1)+; HPLC purity 98.36% (Maxplot), 97.66% (220 nm).

Provenance & Evidence