Potassium Carbonate → Methyl 3-methoxy-4-(6-nitrobenzimidazol-1-ylmethyl)benzoate

HRID 1646351Notes

Reaction equation

HRID 1646351 reaction equation
[N+:1]([C:4]1[CH:5]=[CH:6][C:7]2[NH:11][CH:10]=[N:9][C:8]=2[CH:12]=1)([O-:3])=[O:2].Br[CH2:14][C:15]1[CH:24]=[CH:23][C:18]([C:19]([O:21][CH3:22])=[O:20])=[CH:17][C:16]=1[O:25][CH3:26].C(=O)([O-])[O-].[K+].[K+]>C(C(C)=O)C>[CH3:26][O:25][C:16]1[CH:17]=[C:18]([CH:23]=[CH:24][C:15]=1[CH2:14][N:9]1[C:8]2[CH:12]=[C:4]([N+:1]([O-:3])=[O:2])[CH:5]=[CH:6][C:7]=2[N:11]=[CH:10]1)[C:19]([O:21][CH3:22])=[O:20]

Participants

5

Procedure

A solution of 6-nitrobenzimidazole (2.0 g.) and methyl 4-bromomethyl-3-methoxybenzoate (B) (3.5 g.) in methyl ethyl ketone (61 ml.) was treated with potassium carbonate (1.9 g.) and then heated under reflux for 24 hours. The solvent was then evaporated. The residue was extracted with ethyl acetate and inorganic material removed by filtration. The filtrate was evaporated. The resultant residue was purified by flash chromatography on a 6×30 cm. silica gel column using 1:1 v/v hexane:ethyl acetate as the eluent to give methyl 3-methoxy-4-(6-nitrobenzimidazol-1-ylmethyl)benzoate (K) (1.07 g., 26%); NMR: 3.9 (s,3 H, OCH3), 4.0 (s,3 H, OCH3), 5.7 (s,2 H, NCH2), 7.4 (d, 1 H, Ar), 7.8 (d,1 H, H4 -benzimidazole), 8.1 (dd, 1 H, H5 -benzimidazole), 8.6 (br s,2 H2,7 -benzimidazole).

Workup

  1. temperatureheated
  2. temperatureunder reflux for 24 hours
  3. customThe solvent was then evaporated
  4. extractionThe residue was extracted with ethyl acetate and inorganic material
  5. customremoved by filtration
  6. customThe filtrate was evaporated
  7. customThe resultant residue was purified by flash chromatography on a 6×30 cm

Sources & evidence

ORD record
ord-cb884c7bb6ef446ea52a202b8d93f073
Source dataset
uspto-grants-1993_01
Patent number
US05179112

Reaction notes

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