PREPARATION OF 1,2,3,4-TETRACHLOROBENZENE-5,6-DITHIOL

摘要

PURPOSE:To obtain the titled compound useful as a chelating agent for metallic ions or analytical reagents in high yield at a mild reaction temperature, by reacting 1,2,3, 4-tetrachloro-5,6-dibromobenzene with sodium hydrosulfide. CONSTITUTION:1,2,3,4-Tetrachloro-5,6-dibromobenzene is reacted with sodium hydrosulfide in the presence of a polar organic solvent, e.g. an alcohol or DMSO, at 100-145 deg.C, preferably 110-120 deg.C, to give the titled compound. The use of iron powder or an iron salt, e.g. iron chloride or bromide, in the reaction system suppresses side reactions to give the titled compound in high yield. The method is more advantageous than the use of hexachlorobenzene as a raw material.