Sodium Hydroxide → 2H-Benzimidazol-2-one, 1,3-dihydro-6-chloro-1-(4-chlorophenyl)-

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).

1. customA small exotherm produced a final temperature of 33° C
2. customSolids were removed by filtration
3. customthe biphasic system was then evaporated to a volume of about 100 ml
4. additiondiluted with water (500 ml)
5. filtrationThe tilted product was then recovered by filtration
6. customdried at 80° C.
7. customThe product was recovered in a yield of better than 99 percent of theoretical and
8. custommelted at 239° C. (recrystallized from toluene)

ORD record

ord-618b7efe2a494f8ebcbe103279beb1cc

Source dataset

uspto-grants-1981_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04275215