p-Toluenesulfonic acid monohydrate → 7-[1-Ethylprop-1-en-1-yl]-2-(mesitylmethyl)-1-methyl-1H-benzimidazole
Reaction equation
[C:1]1([CH3:26])[CH:6]=[C:5]([CH3:7])[CH:4]=[C:3]([CH3:8])[C:2]=1[CH2:9][C:10]1[N:14]([CH3:15])[C:13]2[C:16]([C:20](O)([CH2:23][CH3:24])[CH2:21][CH3:22])=[CH:17][CH:18]=[CH:19][C:12]=2[N:11]=1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C(C)=CC=CC=1.C(OCC)(=O)C>[CH2:23]([C:20]([C:16]1[C:13]2[N:14]([CH3:15])[C:10]([CH2:9][C:2]3[C:1]([CH3:26])=[CH:6][C:5]([CH3:7])=[CH:4][C:3]=3[CH3:8])=[N:11][C:12]=2[CH:19]=[CH:18][CH:17]=1)=[CH:21][CH3:22])[CH3:24]Participants
5
Reactant 2
Product 1
Reagents, catalysts & solvents 2
Procedure
A solution of 3-[2-(mesitylmethyl)-1-methyl-1H-benzimidazol-7-yl]pentan-3-ol (200 mg, 0.571 mmol) and p-toluenesulfonic acid monohydrate (326 mg, 1.71 mmol) in xylene (10 mL) was refluxed for 3 hr. After cooling, the mixture was diluted with ethyl acetate (50 mL) and washed with saturated aqueous sodium bicarbonate solution (30 mL) and brine (30 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with 10-20% ethyl acetate/n-hexane gradient mixture to give the title compound (180 mg, 0.542 mmol, 95%, as a mixture of geometric isomers) as a colorless solid.
Workup
- temperatureAfter cooling
- washwashed with saturated aqueous sodium bicarbonate solution (30 mL) and brine (30 mL)
- dry with materialThe organic layer was dried over anhydrous sodium sulfate
- concentrationconcentrated in vacuo
- customThe residue was purified by silica gel column chromatography
- washeluting with 10-20% ethyl acetate/n-hexane gradient mixture
Sources & evidence
- ORD record
- ord-4156e820019b42d6a64b96a7c41f8f71
- Source dataset
- uspto-grants-2011_10
- Patent number
- US08039500B2
Reaction notes
Loading…