METHOD FOR PREPARING COMPOUNDS OF 4,4'-DICHLORO-ORTHO-HYDROXYDIPHENYL ESTER Russian patent published in 2004 - IPC

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing 4,4'-dichloro-o-hydroxydiphenyl ester of the formula 1) wherein Hal₁ and Hal₂ means chlorine atom. Method involves halogenation of alkoxyphenol of the formula (6) wherein R₁ means (C₁-C₅)-alkyl (stage a₁). The stage (a₁) is carried out using elementary chlorine or sulfuryl chloride in the presence of an organic solvent taken among aromatic, aliphatic or cycloaliphatic hydrocarbon and interaction of prepared halide-substituted phenol of the formula (5): wherein R₁ and Hal₁ have values indicated above with para-dihalogenbenzene of the formula (4a) wherein Hal₂ means chlorine atom and Hal₃ means bromine atom in the presence of copper and/or copper salts as a catalyst and alkaline metal hydroxide taken in the amount from 20 to 80 mass.% of theoretical amount of the parent components to yield the corresponding diphenyl ester of the formula (2): wherein R₁, Hal₁ and Hal₂ have values indicated above (stage a₂) followed by cleaving the prepared diphenyl ester of the formula (2) (stage a₃). Method provides preparing 4,4'-dichloro-o-hydroxydiphenyl ester without by-side reactions and enhanced economy.

EFFECT: improved preparing method.

2 cl, 4 ex