1-benzyl-4-[N-(2-nitrophenyl)-N-acetylamino]-piperidine hydrobromide → 2-Methyl-1-(4-piperidinyl)-1H-benzimidazole

HRID 647823Notes

Reaction equation

HRID 647823 reaction equation
Br.C([N:9]1[CH2:14][CH2:13][CH:12]([N:15]([C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][C:20]=2[N+:25]([O-])=O)[C:16](=O)[CH3:17])[CH2:11][CH2:10]1)C1C=CC=CC=1.[H][H]>[C].[Pd].CO>[CH3:17][C:16]1[N:15]([CH:12]2[CH2:13][CH2:14][NH:9][CH2:10][CH2:11]2)[C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][C:20]=2[N:25]=1

Participants

5

Reactant 2

HCID 204833491-benzyl-4-[N-(2-nitrophenyl)-N-acetylamino]-piperidine hydrobromideHCID 178418361HCID 178418361, compound

Product 1

HCID 129618492-Methyl-1-(4-piperidinyl)-1H-benzimidazoleYield 91.3%

Reagents, catalysts & solvents 2

HCID 178418390HCID 178418390, compoundCatalystHCID 887MethanolSolvent

Procedure

In this reference example, 14.8 g of 1-benzyl-4-[N-(2-nitrophenyl)-N-acetylamino]-piperidine hydrobromide obtained in the same manner as that of Refernce Example 4, 250 ml of methanol and 1.0 g of 5% palladium carbon are mixed and stirred at room temperature under the atmospheric pressure in the current of hydrogen for 12 hours. The resultant reaction mixture is filtered. The filtrate is mixed with 29 ml of concentrated hydrochloric acid and stirred overnight. The reaction solution is concentrated and the residue is dissolved in 50 ml of water. The solution is adjusted to pH 11.0 with 1 N aqueous sodium hydroxide. The solution is extracted with 50 ml of chloroform three times, and the extract is washed with 20 ml of a saturated aqueous sodium chloride and dried. The extract is freed from the solvent by distillation. The residue is mixed with n-hexane and stirred for crysallization. The crystals are separated by filtration, recrystallized from a mixed solvent of n-hexane and ethanol to obtain 6.7 g of 4-(2-methyl-benzimidazol-3-yl)-piperidine.

Workup

  1. additionare mixed
  2. customThe resultant reaction mixture
  3. filtrationis filtered
  4. additionThe filtrate is mixed with 29 ml of concentrated hydrochloric acid
  5. concentrationThe reaction solution is concentrated
  6. dissolutionthe residue is dissolved in 50 ml of water
  7. extractionThe solution is extracted with 50 ml of chloroform three times
  8. washthe extract is washed with 20 ml of a saturated aqueous sodium chloride
  9. customdried
  10. distillationThe extract is freed from the solvent by distillation
  11. additionThe residue is mixed with n-hexane
  12. stirringstirred for crysallization
  13. customThe crystals are separated by filtration
  14. customrecrystallized from a mixed solvent of n-hexane and ethanol

Sources & evidence

ORD record
ord-17f36f77b8744182836ed65cd95017c6
Source dataset
uspto-grants-1983_10
Patent number
US04410528

Reaction notes

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