URATE COMPLEXES OF DIPOSITIVE FIRST ROW TRANSITION-METAL IONS

The following complexes were prepared by reacting uric acid (uaH(2)) with 3d metal(II) perchlorates in non-aqueous media: trans-[Mn(uaH)(2)(OH2)(4)], octahedral, and [Co-(uaH)(2)(OH2)(2)], tetrahedral, both involving O(8)-bound hydrogenurate; [Cu(ua)(OH2)(3)], tetrahedral, with the urate dianion binding via a ring nitrogen; and [Ni-2(uaH)(2)-(uaH(2))(ClO4)(2)(H2O)(3)], formulated as a pentacoordinated linear polymetric species, involving bidentate bridging hydrogenurate, binding through O(8) and a ring nitrogen.