Process for the preparation of p-dichlorobenzene
AssigneeBayer Aktiengesellschaft
InventorsFranz-Josef Mais, Helmut Fiege
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Abstract
Dichlorobenzene having an increased p-content and a greatly reduced m-content is obtained by ring chlorination of benzene or chlorobenzene in the presence of Friedel-Crafts catalysts if the reaction is carried out in the presence of co-catalysts of the formula (I) ##STR1## wherein X represents fluorine, chlorine, bromine, trifluoromethyl or pentafluoroethyl and A represents 2 hydrogen atoms or the group --CH.dbd.CH--CH.dbd.CH--.
Claims10
A process for the preparation of dichlorobenzene having an increased p-content and a very greatly reduced m-content by ring chlorination of benzene or chlorobenzene with chlorine in the presence of a catalytic amount of a Friedel-Crafts catalyst and a co-catalyst in the liquid phase, wherein the co-catalyst has the following formula ##STR7## in which X represents fluorine, chlorine, bromine, trifluoromethyl or pentafluoroethyl and
- A represents 2 hydrogen atoms or the group --CH.dbd.CH--CH.dbd.CH--
- and wherein the reaction is carried out at a temperature between the solidification point and the boiling point of the reaction mixture.
Dependencies are inferred from the claim text.