Methanesulfonyl chloride → (E)-5-Methysulfonylamino-1-(2-pyridyl)-2-styryl-1H-benzimidazole

To a stirred solution of (E)-5-amino-1-(2-pyridyl)-2-styryl-1H-benzimidazole (162 mg, 0.52 mmol) in dichloromethane (3 ml) and pyridine (1 ml) was added a solution of methanesulfonyl chloride (63 mg, 0.55 mmol) in dichloromethane (2 ml) dropwise. The reaction mixture was stirred for 2 h at room temperature and then partitioned between ethyl acetate (50 ml) and saturated aqueous sodium bicarbonate solution (50 ml). The organic phase was separated and the aqueous phase was extracted with ethyl acetate (50 ml). The combined extracts were washed with brine (50 ml), dried (sodium sulfate) and concentrated in vacuo to give brown oil. It was purified by column chromatography (silica gel, 20 g; n-hexane/ethyl acetate (5/1)). Recrystallization of the residue from ethyl acetate afforded 70 mg (34%) of the titled compound as off white solids.

1. custompartitioned between ethyl acetate (50 ml) and saturated aqueous sodium bicarbonate solution (50 ml)
2. customThe organic phase was separated
3. extractionthe aqueous phase was extracted with ethyl acetate (50 ml)
4. washThe combined extracts were washed with brine (50 ml)
5. dry with materialdried (sodium sulfate)
6. concentrationconcentrated in vacuo
7. customto give brown oil
8. customIt was purified by column chromatography (silica gel, 20 g; n-hexane/ethyl acetate (5/1))
9. customRecrystallization of the residue from ethyl acetate

ORD record

ord-b3c755b7b7f14b1a95869829c9d54def

Source dataset

uspto-grants-2001_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06310079B1