| abstract |
A process for the preparation of a substituted 1-phenyl-2,2,2-trihalo-ethanol ester of the formula <IMAGE> in which R is alkyl, halogenoalkyl, alkoxy, cycloalkyl or optionally substituted phenyl, benzyl, phenoxy, or phenylsulfonyl, X is halogenoalkyl with 1-3 carbon atoms and 1-3 halogen atoms, Y is halogen, cyano, nitro, alkyl, alkoxy, alkylmercapto, sulfoalkoxy or optionally substituted methylenedioxy, and N IS AN INTEGER FROM 0 TO 3, COMPRISING REACTING A COMPOUND OF THE FORMULA <IMAGE> WITH A HALOGENATED ALDEHYDE OF THE FORMULA X CHO in the presence of a Friedel-Crafts catalyst at a temperature of about -70 to +100 DEG C thereby to form a complex alcoholate, and reacting the complex alcoholate with an acid halide of the formula <IMAGE> OR WITH A CORRESPONDING ACID ANHYDRIDE AT A TEMPERATURE OF ABOUT -70 TO +100 DEG C. The reaction with the acid halide or anhydride is preferably carried out in the presence of a solvent or diluent, sodium sulfate hydrate is added to the final reaction solution and the resulting mixture of sodium sulfate and basic aluminum halide is filtered off. The products are known insecticides. |