Phosgene → 1-cyclobutyl-2-oxo-2,3-dihydro-1H-benzoimidazole-5-carboxylic acid methyl ester

Participants

Reaction Steps

To a solution of 3-amino-4-cyclobutylamino-benzoic acid methyl ester (15.94 g, 72.3 mmol) in dichloromethane (250 ml) at 23 C was added phosgene (38.3 ml of a 20% solution in toluene) dropwise over 30 minutes. The reaction was allowed to stand for 2 hours then was diluted with water and extracted with ethyl acetate. The organic layer was dried with sodium sulfate and concentrated in vacuo to give 17.01 g of 1-cyclobutyl-2-oxo-2,3-dihydro-1H-benzoimidazole-5-carboxylic acid methyl ester.

Provenance & Evidence