Water → methyl 2-chloro-1H-1,3-benzodiazole-7-carboxylate

Participants

Reaction Conditions

Reaction Steps

Phosphorus oxychloride (8.5 g, 55.6 mmol) was added to methyl 2-oxo-2,3-dihydro-1H-benzimidazole-4-carboxylate (1.03 g, 5.36 mmol) (reference: WO 2006/116412 A2), and the mixture was stirred at 85° C. for four hours. The reaction solution was diluted with ethyl acetate and THF, slowly added to cold water and neutralized with sodium bicarbonate. The separated organic layer was washed with brine and dried over anhydrous sodium sulfate. Following concentration under reduced pressure, the residue was dissolved in toluene and the insoluble matter was removed. Concentration under reduced pressure gave 800 mg of the title compound as an oily substance. The resulting compound was used for the next reaction without purification.

Provenance & Evidence