Triethylamine → N,N-Dimethyl-4,5,6,7-tetrahydro-1H-benzimidazole-1-sulfonamide

Participants

Reaction Steps

To solution of 4,5,6,7-tetrahydro-1H-benzoimidazole (1.9992 g, 16.4 mmol) and triethylamine (4.60 mL, 32.8 mmol) in CH2Cl2 (20 mL) at 0° C. was added dropwise a solution of dimethyl sulfamoyl chloride (1.76 mL, 16.4 mmol) in CH2Cl2 (10 mL). The reaction was warmed to room temperature and stirred for 3.5 hours. CH2Cl2 (80 mL) was added and the organic phase was washed with distilled water (1×80 mL). The aqueous washing was extracted with CH2Cl2 (2×40 mL), and the combined organic extracts were washed with brine (1×80 mL), dried (Na2SO4), and concentrated. Purification of the crude material by column chromatography on silica gel (2:1 hexanes-EtOAc) provided 2.89 g (77%) of 4,5,6,7-tetrahydro-benzoimidazole-1-sulfonic acid dimethylamide as a white solid. 1H NMR (CDCl3) δ 1.77-1.86 (m, 4H), 2.58-2.61 (m, 2H), 2.72 (t, 2H, J=6 Hz), 2.87 (s, 6H), 7.77 (s, 11H).

Provenance & Evidence