Dimethylformamide → 1-(Methylsulfonyl)-1H-Benzimidazol-2-Amine

Participants

Reaction Steps

2-amino-benzimidazole (1.0 g, 7.5 mmol) was dissolved in 15 mL of anhydrous CH2Cl2 and 3 mL anhydrous DMF and cooled to ˜0° C. Trethylamine (1.6 mL, 1.5 eq.) was added followed by an addition of methanesulfonylchloride (580 μL, 7.5 mmol) over ˜1 minute. After 1 minute at ˜0° C., the reaction was warmed to RT. After 1 hour the reaction was quenched with water, and partitioned between a saturated sodium bicarbonate solution and CH2Cl2. The aqueous layer was extracted with CH2Cl2 and the combined organic layers were washed with water (2 times), brine then dried over NaSO4, filtered and the solvent was removed in vacuo to give 455 mg of N-methanesulfonyl-2-aminobenzimidazole. HPLC shows the material to be 91% pure, (ret. time=3.70). LCMS: obs. M+H@ 212.1 amu. The material was carried on without purification.

Provenance & Evidence