N,N'-Dimethylethylenediamine → 4-Iodo-1H-benzimidazole

Beteiligte Stoffe

Reaktionsschritte

Two reactions were set up as follows: A mixture of 4-bromo-1H-benzimidazole (725 mg, 3.68 mmol), sodium iodide dihydrate (1.37 g, 7.36 mmol), copper(I) iodide (70 mg, 0.37 mmol) and N,N′-dimethylethylenediamine (78 μL, 65 mg, 0.74 mmol) in dioxane (8 mL) was irradiated at 150° C. in a microwave reactor for 2.5 hours. The two reaction mixtures were combined, diluted with water (90 mL) and conc. ammonia (20 mL), then extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with water (20 mL), then with saturated sodium chloride solution (50 mL), dried (MgSO4) and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel, eluting with ethyl acetate, yielding the product as a yellow-white solid (1.40 g, 78%). 1H NMR (400 MHz, d6-DMSO): δ 12.72 (1H, s), 8.28 (1H, s), 7.61-7.53 (2H, m), 7.01 (1H, t, J=7.8 Hz); m/z (ES+) 245 [MH+].

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