Mononuclear and binuclear chelates of biacetylmonoxime picolinoylhydrazone

Mononuclear and binuclear chelates of biacetylmonoxime picolinoylhydrazone (H2BMPcH) with Cr-III, Fe-III, Co-II, Ni-II, Cu-II, Zn-II, Cd-II, Pd-II and UO22+ have been prepared. Elemental analyses, molar conductivities, spectr al (u.v., visible, i.r., n.m.r., e.s.r.), thermal (t.g., d.t.g., d.t.a.) an d magnetic susceptibility measurements have been used to characterize the c helates. The i.r. spectral data indicate that H2BMPcH behaves in a bidentat e, tridentate and/or tetradentate manner and the hydrazonic azomethine nitr ogen constituents the chelating backbone in all chelates. Based on magnetic and spectroscopic data, the structures for the chelates are proposed as fo llows: tetrahedral for [Co(HBMPcH)(H2O)]Cl, octahedral for [Co(HBMPcH)(2)], [Cr(HBMPcH)Cl(H2O)](2)Cl-2, [Fe(HBMPcH)Cl-(H2O)](2)Cl-2, [Ni(BMPcH)(H2O)(2 )], square-planar for (Ni(HBMPcH)Cl], [Pd(HBMPcH)Cl], [Cu(HBMPcH)(H2O)]Cl a nd tetragonally distorted octahedral for [Cu(BMPcH)(H2O)(2)](2) chelates. G enerally, the solid metal acetate complexes have a unique decomposition exo therm profile which can be used as a rapid and sensitive tool for the detec tion of acetate-containing complexes.