Ethanol → HCID 178470645, compound

HRID 397814Notes

Reaction equation

HRID 397814 reaction equation
[NH:1]1[C:5]2[CH2:6][CH2:7][CH:8]([CH2:10][C:11]([OH:13])=[O:12])[CH2:9][C:4]=2[N:3]=[CH:2]1.S(Cl)(Cl)=O.[CH2:18](O)[CH3:19]>>[CH2:18]([O:12][C:11](=[O:13])[CH2:10][CH:8]1[CH2:7][CH2:6][C:5]2[NH:1][CH:2]=[N:3][C:4]=2[CH2:9]1)[CH3:19]

Participants

4

Reactant 3

HCID 702EthanolHCID 24386Thionyl ChlorideHCID 178525015HCID 178525015, compound

Product 1

HCID 178470645HCID 178470645, compound

Procedure

A mixture of 4,5,6,7-tetrahydro-1H-benzimidazole-5-acetic acid (2.2 g, 10 mmol) and ethanol (40 ml) was placed on an ice-bath and thionylchloride (1.78 g, 15 mmol) was added dropwise. When addition was complete, the mixture was stirred for 30 minutes and then heated at reflux for 5 hours. The solvent was evaporated and the residue was re-evaporated with acetonitrile and then stirred with acetonitrile (40 ml) and triethylamine (1.5 ml). The resulting mixture was filtered and the solid was discarded. From the filtrate the solvent was evaporated to give crude 4,5,6,7-tetrahydro-1H-benzimidazole-5-acetic acid ethyl ester. This ester was dissolved in acetonitrile (40 ml) and triethylamine (1.5 ml, 11 mmol) was added followed by portionwise addition of triphenylmethylchloride (2.8 g, 10 mmol). When addition was complete the mixture was stirred overnight at ambient temperature. The mixture was filtered and from the filtrate the solvent was evaporated. The residue was dissolved in ethyl acetate (25 ml) and left for crystallisation. The solid formed was isolated and discarded and from the filtrate the solvent was evaporated. The residue was dissolved in THF (40 ml) and the mixture was placed under an atmosphere of nitrogen. 1 N Lithiumaluminium hydride in THF (6 ml, 6 mmol) was added dropwise. When addition was complete the mixture was stirred at ambient temperature for 3 hours. The mixture was quenched with small amounts of water and 4 N Sodium hydroxide and ethyl acetate was added (50 ml). The solid was removed by filtration and the filtrate was dried (magnesium sulphate). The solvent was evaporated to give a residue that was crystallised from ethyl acetatete (20 ml). This afforded 1.3 g (32%) of 2-(1(3)-triphenylmethyl-4,5,6,7-tetrahydro-1H-benzimidazol-5-yl)ethanol.

Workup

  1. customwas placed on an ice-bath
  2. additionWhen addition
  3. temperatureheated
  4. temperatureat reflux for 5 hours
  5. customThe solvent was evaporated
  6. customthe residue was re-evaporated with acetonitrile
  7. stirringstirred with acetonitrile (40 ml) and triethylamine (1.5 ml)
  8. filtrationThe resulting mixture was filtered
  9. customFrom the filtrate the solvent was evaporated

Sources & evidence

ORD record
ord-4f5737ded80940ee888850238594d96b
Source dataset
uspto-grants-2003_08
Patent number
US06610721B2

Reaction notes

Loading…