Ethanol → 5-Acetyl-1-[3-(1-methylpiperidin-3-yl)phenyl]benzimidazole

HRID 324736Notes

Reaction equation

HRID 324736 reaction equation
[C:1]([C:4]1[CH:23]=[CH:22][C:7]([NH:8][C:9]2[CH:14]=[CH:13][CH:12]=[C:11]([C:15]3[CH2:20][N:19]([CH3:21])[CH2:18][CH2:17][CH:16]=3)[CH:10]=2)=[C:6]([N+:24]([O-])=O)[CH:5]=1)(=[O:3])[CH3:2].[CH2:27](O)C>[Pd]>[C:1]([C:4]1[CH:23]=[CH:22][C:7]2[N:8]([C:9]3[CH:14]=[CH:13][CH:12]=[C:11]([CH:15]4[CH2:16][CH2:17][CH2:18][N:19]([CH3:21])[CH2:20]4)[CH:10]=3)[CH:27]=[N:24][C:6]=2[CH:5]=1)(=[O:3])[CH3:2]

Participants

4

Reactant 2

HCID 702EthanolHCID 227418634-acetyl-N-[3-(1-methyl-1,2,3,6-tetrahydropyrid-5-yl)phenyl]-2-nitroaniline

Product 1

HCID 227418345-Acetyl-1-[3-(1-methylpiperidin-3-yl)phenyl]benzimidazoleYield 50%

Reagents, catalysts & solvents 1

HCID 23938PalladiumCatalyst

Conditions

Temperature
80 °C

Procedure

To a solution of 4-acetyl-N-[3-(1-methyl-1,2,3,6-tetrahydropyrid-5-yl)phenyl]-2-nitroaniline (6, Ex. 12a) (1 g, 3 mmol) in ethanol (50 ml) was added a catalytic amount of palladium on charcoal and the mixture was hydrogenated at ambient pressure over night. The reaction mixture was filtered through celite and the filtrate was concentrated under reduced pressure. To this concentrate formic acid (10 ml) was added and the resulting solution was stirred at 80° C. over night. Excess formic acid was removed by evaporation. The residue was dissolved in water and rendered alkaline by addition of solid sodium carbonate. Extraction with ethyl acetate and treatment of the extract with activated carbon in ethanol afforded 5-acetyl-1-[3-(1-methylpiperidin-3-yl)phenyl]-benzimidazole (9) (0.5 g, 50%) as an oil. m/e 333.

Workup

  1. waitthe mixture was hydrogenated at ambient pressure over night
  2. filtrationThe reaction mixture was filtered through celite
  3. concentrationthe filtrate was concentrated under reduced pressure
  4. additionTo this concentrate formic acid (10 ml) was added
  5. customExcess formic acid was removed by evaporation
  6. dissolutionThe residue was dissolved in water
  7. additionby addition of solid sodium carbonate
  8. extractionExtraction with ethyl acetate and treatment of the
  9. extractionextract with activated carbon in ethanol

Sources & evidence

ORD record
ord-d59b78b176b14ed2bc224d08e33d3d1a
Source dataset
uspto-grants-2001_04
Patent number
US06218547B1

Reaction notes

Loading…