1,2-Dichloroethane → 1-(2-Hydroxyethyl)-5,6-dimethylbenzimidazole
Reaction equation
[CH3:1][C:2]1[C:10]([CH3:11])=[CH:9][C:5]2[N:6]=[CH:7][NH:8][C:4]=2[CH:3]=1.[H-].[Na+].[CH2:14](Cl)[CH2:15]Cl.[OH2:18]>CN(C)C=O>[OH:18][CH2:14][CH2:15][N:6]1[C:5]2[CH:9]=[C:10]([CH3:11])[C:2]([CH3:1])=[CH:3][C:4]=2[N:8]=[CH:7]1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
A 1.46 g amount of 5,6-dimethylbenzimidazole was dissolved in 50 ml of dry N,N-dimethylformamide, 0.96 g of NaH was added to the solution, and the mixture was stirred in an ice-water bath for 30 minutes. Then to the mixture was added dropwise 5 ml of ethylene chloride, the mixture was stirred at room temperature for 15 hours, and the reaction was further carried out for 24 hours while adding 0.78 g of NaH. The reaction was stopped by an addition of 50 ml of water, and the obtained reaction mixture was washed with n-hexane, diluted with water, adjusted to a pH of 2.5 with HCl, and then applied to an ion exchange column (Dowex 50 (hydrogen ion form)). An elution was effected successively with water, 30% ethanol, and ammoniacal 30% ethanol, and the fractions eluted with ammoniacal 30% ethanol were concentrated to dryness under a reduced pressure to give crude 1-(2-hydroxy-ethyl)-5,6-dimethylbenzimidazole. The conversion to this compound from 5,6-dimethylbenzimidazole was found to be 75% by an assay according to thin layer chromatography.
Workup
- stirringthe mixture was stirred at room temperature for 15 hours
- waitthe reaction was further carried out for 24 hours
- customthe obtained reaction mixture
- washwas washed with n-hexane
- additiondiluted with water
- washAn elution
- washthe fractions eluted with ammoniacal 30% ethanol
- concentrationwere concentrated to dryness under a reduced pressure
Sources & evidence
- ORD record
- ord-cd336d44e5614790a32d00a0a59f292f
- Source dataset
- uspto-grants-1995_04
- Patent number
- US05405839
Reaction notes
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