Hydrochloric Acid → N-(4-[2-(1-oxo-isoindoline-2-carboxamido)-ethyl]-benzenesulfonyl)-N'-butyl-urea

Participants

Reaction Steps

3 g of N-(4-[2-amino-ethyl]-benzenesulfonyl)-N'-butyl-urea (melting point 210°-212° C., prepared by saponification of N-(4-[2-acetylamino-ethyl]-benzenesulfonyl)-N'-butyl-urea with sodium hydroxide solution) are dissolved with 0.4 g of sodium hydroxide in 50 ml of water and 50 ml of acetone and, while stirring, a solution of 2 g of 1-oxo-isoindoline-2-carboxylic acid chloride (melting point 119°-121° C., prepared from 1-oxo-isoindoline sodium and phosgene) in about 50 ml of acetone is added. The temperature of the mixture increases slightly. Stirring is continued for 2 hours at room temperature, whereupon the residue is acidified with dilute hydrochloric acid. The precipitate is reprecipitated from dilute ammonia and recrystallized from dilute acetone. The N-(4-[2-(1-oxo-isoindoline-2-carboxamido)-ethyl]-benzenesulfonyl)-N'-butyl-urea melts at 188°-190° C.

Provenance & Evidence