Silver complexes tetraaza macrocyclic ligands

Disproportionation of Ag(I) to silver metal and Ag(II) in the presence of tetraaza macrocyclic ligands depends upon the ring size of the macrocycle thus while 14-, 15-, and 16-membered rings generally cause disproportionation, larger rings do not. Two mixed-valence complexes [Ag (tmc) (BF4)] [Ag 6(C2) (CP3C02)5 (H2O)]. H2O... 

Reaction of silver(I) with macrocyclic tetraaza ligands has been found to be a facile process for forming silver(II) complexes.450,451 Metallic silver was a by-product in each of these reactions. In dry acetonitrile, however, no disproportionation occurred and with (57) a white silver(I) complex precipitated. The necessity for water to be present for disproportionation was shown by the fact that if this complex was then added to water or aqueous methanol solutions, disproportionation then readily occurred.451... 

Macrocyclic tetraaza ligand complexes of silver have been found for oxidation states +1, +2 and +3. In the presence of water, the silver(I) complexes generally disproportionate to silver(II) depositing silver metal. Some of the silver(II) species obtained have been oxidized, both chemically (N0C104-H20 in acetonitrile) and electrochemically, to silver(III) complexes of substantial stability.496... 

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