Dimethylformamide → N,N'-Dicyclohexylurea

Participants

Reaction Conditions

Reaction Steps

Then, 11.1 g of 1-(3-carboxyphenyl)-5-mercaptotetrazole and 7.6 g of 1-formyl-2-(4-aminophenyl)hydrazine were dissolved in 50 ml of dimethylformamide and a solution of 10.3 g of dicyclocarbodiimide in 5 ml of dimethylformamide was added dropwise to the solution with stirring at 0° C. under a nitrogen atmosphere over a period of 15 minutes. Thereafter, the mixture was stirred for 1 hour and for 2 hours at 25° C. Dicyclohexylurea formed was removed by filtration and the filtrate was added to 1.5 liters of ice water. Crude crystals thus deposited were collected by filtration and dispersed in 100 ml of methanol under heating for 15 minutes. The reaction mixture was cooled to room temperature and filtered to provide 9.6 g of desired Compound 1. The yield was 54% and the melting point was 198°-200° C.

Provenance & Evidence