PHOTOCHEMICAL-REACTIONS OF MOLYBDENUM AND TUNGSTEN OCTACYANOMETALLATES(IV) IN ACIDIC AQUEOUS-MEDIA CONTAINING 2,2'-BIPYRIDYL OR 1,10-PHENANTHROLINE

The reaction scheme of acidic photolysis of [M(CN)(8)](4-) (M = Mo or W) in the presence of 2,2'-bipyridyl (bipy) or 1,10-phenanthroline (phen) based on previous reports, and the present results, is given. In this scheme the formation of [M(CN)(6)(N-N)](2-) (M = Mo or W), postulated in the literature to be a main product of photoexcitation of [M(CN)(8)](4-) in the presence of bipy or phen, has definitively been excluded. The main cyano-polypyridyl species formed are [MO(CN)(3)(N-N)](-) ions which, in acidic solution, undergo further reactions. A new product, [MoO(CN)(2)(N-N)(2)], resulting from thermal replacement of the cyanide ligand by polypyridyl, has been detected.