Hydrogen Peroxide → 2-(2,6-Difluorophenyl)-1-[(2,6-difluorophenyl)methyl]benzimidazole-4-carboxamide

関与物質

反応手順

To 1-(2,6-Difluorobenzyl)-2-(2,6-difluorophenyl)benzimidazole-4-carbonitrile (Example 105) (1.10 g, 2.88 mmol) dissolved in ethanol (100 mL) and 3 M Na2CO3 (10 mL) was added 30% hydrogen peroxide (10 mL). After stirring overnight at room temperature, the reaction was concentrated. The residue was then redissolved in EtOAc, and washed with NaHSO4(10% soln), NaHCO3 (sat. aq) and NaCl (sat. aq). The combined washings were dried (Na2SO4), filtered and concentrated. The crude product was purified by flash chromatography eluting with 2% methanol/CH2Cl2 and recrystallization from methanol, yielding white crystals of 1-(2,6-difluorobenzyl)-2-(2,6-difluorophenyl)benzimidazole-4-carboxylic acid amide (0.83 g, 2.08 mmol, 72% yield). M.p. 260-261° C. 1H-NMR (200 MHz, CD2Cl2): δ 8.10 (dd, J=1.1, 7.7 Hz, 1H, H5), 7.71 (br d, J=8.1 Hz, 1H, H7), 7.59 (m, 1H, H4′), 7.43 (dd, J=7.7, 8.1 Hz, 1H, H6), 7.28 (m, 1H, H4″), 7.13 (m, 2H, H3′,5′), 6.84 (m, 2H, H3″,5″), 5.43 (s, 2H, CH2PhF2), 1.92 (s, 2H, NH2).

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