Cesium carbonate → 6-(1-Hydroxy-1,3-dihydro-benzo[c][1,2]oxaborol-5-yloxy)-5-methoxymethoxy-nicotinonitrile

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Reaction Conditions

Reaction Steps

To a mixture of 6-chloro-5-methoxymethoxy-nicotinonitrile (0.68 g, 3.42 mmol) and 3H-benzo[c][1,2]oxaborole-1,5-diol (0.56 g, 3.76 mmol) in DMF (10 mL) was added cesium carbonate (2.45 g, 7.52 mmol). The resulting suspension was heated at 80° C. for overnight. DMF was removed under reduced pressure, the residue was diluted with EtOAc (50 mL), washed with water (10 mL) and brine (10 mL), dried over Na2SO4, filtered, and concentrated to give brown oil. Purification was accomplished by flash chromatography on silica gel using 1-100% MeOH/EtOAc gradient elution to yield the title compound (0.40 g, 40%) as a transparent oil. 1H NMR (400 MHz, DMSO-d6) δ ppm 9.23 (s, 1 H), 8.24 (s, 1 H), 8.03 (s, 1 H), 7.77 (d, J=8.6 Hz, 1 H), 7.23 (s, 1 H), 7.14 (d, J=7.4 Hz, 1 H), 5.40 (s, 2 H), 4.98 (s, 2 H), 3.45 (s, 3 H); MS (ES) m/z: 313 (M+1)+.

Provenance & Evidence