Chemische Charakterisierung des [py2X]+-Ions (X = Br, J) / Chemical Characterization of the [py2X]+ Ion (X = Br, J)

Abstract

The chemical behaviour of the [py2X]+ ion in acetonitrile as solvent can be well characterized by its intense charge transfer band. The two pyridine molecules of the ion can be substituted successively by chloride ions, the resulting species being py · XCl and XCl2 -. In the order of stability of the species [py2X]+ < py · XCl < XCl2 - the adduct py · XCl thus is placed near the XCl2 - ion. Consequently even this ion can act as Cl donor against the [py2X]+ ion. The XCl and pyridine arising from this reaction on their part form the adduct py · XCl as well. The ionization of the adduct py · JCl giving [py2J]+ and JCl2 -, as proposed in the literature, cannot be correct.