1,3-dicyclopentylurea

Conditions: temp:220.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2 g of sodium salt of 4-(β-<2-methoxy-5-chlorobenzamido>-ethyl)-benzenesulfonamide and 2.2 g of N,N'-dicyclopentyl-urea (m.p. 248° - 249°C, prepared from cyclopentyl-isocyanate and cyclopentyl-amine) were well mixed in a mortar. The mixture was heated to 220°C for 10 minutes in an Erlenmeyer flask on a pre-heated oil bath. After cooling, the sintered reaction cake was treated with 0.5 %-ammonia. After filtration, the filtrate was acidified and a precipitate was obtained which was separated by suction-filtration and dissolved once more in 0.5 %-ammonia. After filtration, the filtrate was acidified. The precipitate of crude N-[4-(β-<2-methoxy-5-chlorobenzamide>-ethyl)-benzenesulfonyl]-N'-cyclopentyl-urea that had separated was isolated by suction-filtration and dried. By treatment with methanol an at first smeary and then crystalline substance was obtained, which after suction-filtration, was once more recrystallized from methanol. The melting point of N-[4-(β-<2-methoxy-5-chloro-benzamido>-ethyl)-benzenesulfonyl]-N'-cyclopentyl-urea obtained was 182° - 184°C. After cooling After filtration a precipitate was obtained which was separated by suction-filtration dissolved once more in 0.5 %-ammonia After filtration The precipitate of crude N-[4-(β-<2-methoxy-5-chlorobenzamide>-ethyl)-benzenesulfonyl]-N'-cyclopentyl-urea that had separated was isolated by suction-filtration dried By treatment with methanol an at first smeary and then crystalline substance was obtained which after suction-filtration was once more recrystallized from methanol