Process for the iodination of aromatic compounds

摘要

The present invention relates to a process for the preparation of iodinated anilines; in particular, it relates to a process including the direct iodination, with suitably activated iodine, of 3,5-disubstituted anilines to the corresponding 3,5-disubstituted-2,4,6-triiodoanilines, which are useful intermediates for the synthesis of x-ray contrast media, and to the preparation of the contrast media themselves.;

主权项

1. A process for the preparation of 5-amino-2,4,6-triiodoisophthalic acid of formula (II)comprising the iodination of 5-aminoisophthalic acid of formula (I)or a salt thereof with molecular iodine and in the presence of iodic acid as an oxidizing agent, wherein the iodination reaction is carried out in a solvent selected from the group consisting of water, aqueous saline solution, hydroalcoholic mixture of lower alcohols C1-C4 and aqueous mixtures of dioxane or glycols, at a pH lower than 3.5.