Process for the selective chlorination of phenolic compounds.

摘要

Selective chlorination in an ortho position relative to the OH functional group of phenolic compounds in a solvent medium, using gaseous chlorine. More particularly, selective chlorination of 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol or their mixtures with each other and with other chlorophenols, of pyrocatechol, resorcinol, guaiacol, 4-methoxyphenol, 2-ethoxyphenol, 4-ethoxyphenol, 2-hydroxybenzaldehyde and 4-hydroxybenzaldehyde in a chlorinated hydrocarbon and in the presence of an amine. The process provides especially more flexibility in the chlorination of phenol, since it makes it possible to prepare only a single desired isomer instead of a mixture of isomers which are difficult to separate. It also permits the separation of two isomeric chlorophenols by selective chlorination of only one of them.