Synthesis of pyridine-thioethers via mono- and tricationic pyridinium salts

On nucleophilic substitution with S-nucleophiles at room temperature, 1-(4-dimethylamino)-[2,3,5,6-tetrachloropyridin-4-yl]pyridinium chloride (2) yielded tetrachloro-4-sulfanylpyridines and 2,3,5-trichloro-4,6- disulfanylpyridines depending on the reaction conditions. Similarly, the tricationic (3,5-dichloropyridine-2,4,6-triyl)-1,1′,1″-tris[4- (dimethylamino)pyridinium] trichloride 3 was reacted with S-nucleophiles to give the corresponding 3,5-trichloro-2,4,6-trisulfanylpyridines under mild conditions. © 2005 Verlag der Zeitschrift für Naturforschung.