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

HRID 50927Notes

Reaction equation

HRID 50927 reaction equation
[NH2:1][C:2]1[CH:24]=[CH:23][C:5]2[N:6]([C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][N:18]=3)[C:7](/[CH:9]=[CH:10]/[C:11]3[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=3)=[N:8][C:4]=2[CH:3]=1.[CH3:25][S:26](Cl)(=[O:28])=[O:27]>ClCCl.N1C=CC=CC=1>[CH3:25][S:26]([NH:1][C:2]1[CH:24]=[CH:23][C:5]2[N:6]([C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][N:18]=3)[C:7](/[CH:9]=[CH:10]/[C:11]3[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=3)=[N:8][C:4]=2[CH:3]=1)(=[O:28])=[O:27]

Participants

5

Reactant 2

HCID 31297Methanesulfonyl chlorideHCID 22736667(E)-5-Amino-1-(2-pyridyl)-2-styryl-1H-benzimidazole

Product 1

HCID 69943285(E)-5-Methysulfonylamino-1-(2-pyridyl)-2-styryl-1H-benzimidazoleYield 34.5%

Reagents, catalysts & solvents 2

HCID 1049PyridineSolventHCID 6344DichloromethaneSolvent2×

Procedure

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. MW: 390.47; mp: 133.5-134.9° C.; 1H-NMR (CDCl3) δ: 8.79 (1H, dd, J=5.1, 1.8 Hz), 8.02 (1H, d, J=16.1 Hz), 7.99 (1H, ddd, J=7.7,7.7, 1.8 Hz), 7.67 (1H, d, J=2.2 Hz), 7.55-7.46 (4H, m), 7.43 (1H, d, J=8.8 Hz), 7.41-7.30 (3H, m), 7.23 (1H, dd, J=8.8, 2.2 Hz), 7.10 (1H, d, J=16.1 Hz), 6.86 (1H, br.s), 3.00 (3H, s).

Workup

  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

Sources & evidence

ORD record
ord-ecdcbf039e0e41c69fba3ead6cb07c35
Source dataset
uspto-grants-2004_03
Patent number
US06713482B2

Reaction notes

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