Methylamine → 6-(4-Bromo-2-chloro-phenylamino)-7-fluoro-3H-benzoimidazole-5-carboxylic acid methylamide

Beteiligte Stoffe

Reaktionsschritte

6-(4-Bromo-2-chloro-phenylamino)-7-fluoro-3H-benzoimidazole-5-carboxylic acid 10c (0.029 g, 0.076 mmol) is dissolved in N,N-dimethylformamide (1.1 mL). HOBT (0.016 g, 0.10 mmol), triethylamine (0.028 mL, 0.20 mmol), methylamine (0.059 mL, 0.12 mmol, 2 M solution in tetrahydrofuran), and EDCI (0.019 g, 0.10 mmol) are added consecutively to the reaction mixture at room temperature. The solution is stirred at room temperature for 16 hours under N2. The reaction mixture is poured into a reparatory funnel and diluted with ethyl acetate and water and the layers separated. The ethyl acetate layer is washed successively with aqueous saturated NH4Cl (2×), brine (1×), aqueous saturated sodium bicarbonate (2×), water (1×), and brine (1×), dried (MgSO4) and concentrated under reduced pressure. The resulting solid is purified by FCC (eluting with 19:1 methylene chloride:methanol) to yield 0.013 g (42%) of the pure desired product. MS APCI (+) m/z 397, 399 (M+, Br pattern) detected; 1H NMR (400 MHz, DMSO-d6) δ 8.76 (broad s, 1H), 8.69 (m, 1H), 8.41 (s, 1H), 7.76 (s, 1H), 7.63 (d, 1H), 7.30 (dd, 1H), 6.50 (dd, 1H), 2.76 and 2.75 (s and s, 3H total, amide rotamers). 19F NMR (376 MHz, DMSO-d6) −132.69 (s).

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