1,1'-Carbonyldiimidazole → Ethyl 4-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)benzoate

HRID 1921198Notes

Reaction equation

HRID 1921198 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[NH:8][C:9]1[CH:19]=[CH:18][C:12]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[CH:11][CH:10]=1.[C:20](N1C=CN=C1)(N1C=CN=C1)=[O:21]>C1COCC1>[O:21]=[C:20]1[N:8]([C:9]2[CH:19]=[CH:18][C:12]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[CH:11][CH:10]=2)[C:3]2[CH:4]=[CH:5][CH:6]=[CH:7][C:2]=2[NH:1]1

Participants

4

Reactant 2

HCID 682631,1'-CarbonyldiimidazoleHCID 18449398Ethyl 4-[(2-aminophenyl)amino]benzoate

Product 1

HCID 18449399Ethyl 4-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)benzoate

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
75 °C

Procedure

A mixture of ethyl 4-[(2-aminophenyl)amino]benzoate from Step B (442 mg, 1.72 mmol) and 1,1′-carbonyldiimidazole (652 mg, 4.02 mmol) in THF (10 mL) was heated at 75° C. for 3 h. The cooled mixture was partitioned between EtOAc (100 mL) and 10% aqueous citric acid (50 mL). The organic layer was washed with H2O (30 mL), then brine (30 mL), then dried over Na2SO4, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel chromatography, eluting with a gradient of hexane:EtOAc—95:5 to 75:25, to give the title compound. MS: m/z=283 (M+1).

Workup

  1. customThe cooled mixture was partitioned between EtOAc (100 mL) and 10% aqueous citric acid (50 mL)
  2. washThe organic layer was washed with H2O (30 mL)
  3. dry with materialbrine (30 mL), then dried over Na2SO4
  4. filtrationfiltered
  5. concentrationconcentrated under reduced pressure
  6. customThe crude product was purified by silica gel chromatography
  7. washeluting with a gradient of hexane

Sources & evidence

ORD record
ord-c3fd567f2fbc4c4687a85d3af4fd3a26
Source dataset
uspto-grants-2012_05
Patent number
US08173655B2

Reaction notes

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