Prepn. of 2,2-di:chloro-1,3-benzo:dioxole(s) - useful as pesticide intermediates, by reacting 2-unsubstituted 1,3-benzo:dioxole with elementary chlorine

摘要

Prepn. of 2,2-dichloro-1,3-benzodioxoles (I) comprises reacting the corresp. 2-unsubstd.-1,3-benzodioxole (II) with elementary chlorine. R = chlorocarbonyl, F, Cl or Br. Pref. the reaction is performed at 80-180 deg.C, esp. 100-140 deg.C, in an inert solvent, esp. a chlorinated solvent, pref. chlorobenzene, 1,2-dichlorobenaene or tetrachloromethane. Pref. R = chlorocarbonyl. USE/ADVANTAGE - Cpds. (I) are intermediates for pesticides described e.g. in EP 198797 and DE 2819788. The new process avoids the use fo phosphorus pentachloride and is technically, economically and ecologically superior to known processes.