1,3-bis(4-chlorophenyl)urea

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

Procedure: 4,4'-Dichlorocarbanilide (14.1 g, 0.05 mole) and tetra-n-butyl ammonium chloride (0.7 g) were dissolved in a mixture of methylene chloride (150 ml) and methanol (150 ml). To this solution was added a solution (20 ml) of sodium hydroxide (4 g) in water and the resulting biphasic mixture was stirred vigorously before the dropwise addition of a solution of sodium hypochlorite (100 ml, 1 N in 0.1 molar sodium hydroxide) over 15 minutes. A small exotherm produced a final temperature of 33° C. The reaction mixture was then vigorously stirred for 4 hours at room temperature. Solids were removed by filtration and the biphasic system was then evaporated to a volume of about 100 ml, acidified with hydrochloric acid, and then diluted with water (500 ml). The tilted product was then recovered by filtration, dried at 80° C., and identified by infrared spectra. The product was recovered in a yield of better than 99 percent of theoretical and melted at 239° C. (recrystallized from toluene). A small exotherm produced a final temperature of 33° C Solids were removed by filtration the biphasic system was then evaporated to a volume of about 100 ml diluted with water (500 ml) The tilted product was then recovered by filtration dried at 80° C. The product was recovered in a yield of better than 99 percent of theoretical and melted at 239° C. (recrystallized from toluene)

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

Procedure: A solution of sodium hydroxide (4 grams (g)) in water (15 milliliters (ml)) was added to a solution of 4,4'-dichlorocarbanilide (14.1 g, 0.05 mole) in methanol (300 ml). Sodium hypochlorite solution (100 ml, 1 N in 0.1 molar sodium hydroxide) was then added dropwise over 30 minutes to the vigorously stirred reaction mixture, maintaining the temperature below 35° C. by means of an ice bath. Stirring was continued at room temperature for 5 hours after which the small amount of solid present was removed by filtration. The filtrate was evaporated to a volume of about 50 ml, diluted with water (500 ml), and subsequently acidified to a pH of 3 with hydrochloric acid. The product was then filtered, washed with water, dried at 80° C. and identified as 6-chloro-1-(4-chlorophenyl)-2-benzimidazolinone by infrared spectra. The product recovery was 66 percent of theoretical and the product melted at 239° C. (recrystallized from toluene). maintaining the temperature below 35° C. by means of an ice bath after which the small amount of solid present was removed by filtration The filtrate was evaporated to a volume of about 50 ml diluted with water (500 ml) The product was then filtered washed with water dried at 80° C.