Phosphorus pentachloride → HCID 178466243, compound

HRID 2074458Notes

Reaction equation

HRID 2074458 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][C:3]=1[NH:11][C:12](=O)[CH2:13][C:14]1[CH:19]=[CH:18][C:17]([O:20][CH2:21][CH3:22])=[CH:16][CH:15]=1.P(Cl)(Cl)(Cl)(Cl)Cl>C(Cl)(Cl)Cl.O.[OH-].[NH4+]>[CH2:21]([O:20][C:17]1[CH:18]=[CH:19][C:14]([CH2:13][C:12]2[NH:1][C:2]3[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][C:3]=3[N:11]=2)=[CH:15][CH:16]=1)[CH3:22]

Participants

6

Reactant 2

HCID 24819Phosphorus pentachlorideHCID 59799754N-(2-Amino-5-nitro-phenyl)-2-(4-ethoxy-phenyl)-acetamide

Product 1

HCID 178466243HCID 178466243, compound

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6212ChloroformSolvent2×HCID 14923Ammonium HydroxideSolvent

Procedure

N-(2-Amino-5-nitro-phenyl)-2-(4-ethoxy-phenyl)-acetamide 41 (590 mg, 1.871 mmol), Phosphorous pentachloride (390 mg, 1.871 mmol) were dissolved in anhydrous chloroform (20 mL) in a small, argon purged flask fitted with an condenser and magnetic stirbar. The solution was heated to reflux in an oil bath for 4 hours and cooled to room temperature overnight. The mixture was diluted with H2O and chloroform and 2M ammonium hydroxide solution added to adjust pH to 9-10. The mixture was transferred to a separatory funnel and the organic layer collected. The aqueous layer was further extracted with chloroform and the combined organic layers were washed with brine, dried over magnesium sulphate, filtered and concentrated to afford crude. The product was purified using dry silica gel column chromatography eluting with 20 mL portions of solvent system (2.5% 2M NH3 in methanol/95% dichloromethane) to afford a yellow residue 42 2-(4-Ethoxy-benzyl)-5-nitro-1H-benzimidazole. 1H NMR (DMSO) δ: 1.30 (t, 3H, J=6.5), 3.87 (q, 2H, J=7.3), 4.11 (s, 2H), 6.88 (d, 2H, J=8.0), 7.25 (d, 2H, J=7.9), 7.65 (d, 1H, J=8.9), 8.07 (d, 1H, J=9.0), 8.36-8.40 (m, 1H); MS (ESI): 298 (MH+, 100%)

Workup

  1. customfitted with an condenser
  2. temperatureThe solution was heated
  3. temperatureto reflux in an oil bath for 4 hours
  4. additionadded
  5. customThe mixture was transferred to a separatory funnel
  6. customthe organic layer collected
  7. extractionThe aqueous layer was further extracted with chloroform
  8. washthe combined organic layers were washed with brine
  9. dry with materialdried over magnesium sulphate
  10. filtrationfiltered
  11. concentrationconcentrated
  12. customto afford crude
  13. customThe product was purified
  14. washeluting with 20 mL portions of solvent system (2.5% 2M NH3 in methanol/95% dichloromethane)

Sources & evidence

ORD record
ord-a2b153bcfa3a4c59a9c0c9974527216f
Source dataset
uspto-grants-2011_04
Patent number
US07919510B2

Reaction notes

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