反应详情

温度

87.5 °C

190 ml of chlorobenzene, 25 g of (I) and 17 g of N,N-dibromohydantoin are loaded into a 500 ml pyrex round-bottom flask, under nitrogen, and irradiated from the outside with a 300 watt halogen lamp, keeping temperature between 70 and 75° C. for 3 hours. 150 ml of water and 5 g of PEG 6000 are added, heating to 85-90° C for 2 hours. After decanting at 60° C., water is removed and the organic phase is washed with further water (2×100 ml). Chlorobenzene is evaporated off under vacuum at 5 mm/Hg and the residue is taken up with 50 ml of ethyl acetate. The mixture is cooled to 0° C., filtered and dried at 60° C. for 4 hours, to obtain 16 g of (VI), m.p. 110-111° C., with good purity.

1. customtemperature between 70 and 75° C.
2. customfor 3 hours
3. customAfter decanting at 60° C.
4. customwater is removed
5. washthe organic phase is washed with further water (2×100 ml)
6. customChlorobenzene is evaporated off under vacuum at 5 mm/Hg
7. temperatureThe mixture is cooled to 0° C.
8. filtrationfiltered
9. customdried at 60° C. for 4 hours