反应详情

23.8 g of fluorodichloromethanesulphenyl chloride in 100 ml of acetic acid ethyl ester is added dropwise within 20 minutes at -10°C, with vigorous stirring, to a suspension of 22.5 g of 3-(3'-chloro-4'-methylphenyl)imidazolidine-2,4-dione in 400 ml of acetic acid ethyl ester, and after one hour there is also added dropwise, at 0°C in the course of 10 minutes, 14.2 g of triethylamine in 100 ml of acetic acid ethyl ester; the cooling bath is subsequently removed and stirring is continued for 3 hours at room temperature. The triethylamine hydrochloride that has precipitated is filtered off and then washed with 100 ml of acetic acid ethyl ester; the solvent is evaporated off in vacuo to obtain, after recrystallisation in methanol, Compound No. 1 which melts at 166° - 167°C.

1. customthe cooling bath is subsequently removed
2. customThe triethylamine hydrochloride that has precipitated
3. filtrationis filtered off
4. washwashed with 100 ml of acetic acid ethyl ester
5. customthe solvent is evaporated off in vacuo
6. customto obtain
7. customafter recrystallisation in methanol