反应详情

A mixture of dimethyl 2,2′-(4-nitro-2-oxo-1H-benzimidazole-1,3-diyl)diacetate from Step B (270 mg, 0.84 mmol) and 10% Pd/C (50 mg) in MeOH (100 mL) was stirred under an atmosphere of hydrogen (ca. 1 atm). After 2 h, the reaction was filtered through a Celite pad and concentrated in vacuo. The crude solid was dissolved in toluene (3 mL) and p-toluenesulfonic acid monohydrate (2 mg, 0.011 mmol) was added. The mixture was heated at reflux for 30 min and then concentrated in vacuo to give the title compound. MS: m/z=262 (M+1).

1. filtrationthe reaction was filtered through a Celite pad
2. concentrationconcentrated in vacuo
3. dissolutionThe crude solid was dissolved in toluene (3 mL)
4. temperatureThe mixture was heated
5. temperatureat reflux for 30 min
6. concentrationconcentrated in vacuo