Zirconium acetylacetonate complexes

Also increasingly common, as CVD precursors, are many halogen-acetylacetonate complexes, such as trifluoro-acetylacetonate thorium, Th(C5H4F302)4, used in the deposition of thoriated tungsten for thermionic emitters, the trifluoro-acetylacetonates of hafnium and zirconium and the hexafluoro-acetylacetonates of calcium, copper, magnesium, palladium, strontium, and yttrium. 

Zirconium Acetylacetonate Sihca supported Zr(lV) acetylacetonate surface complex [(=SiO)3Zr(acac)] (acac = MeCOCHCOMe) catalyzes transesterification reactions [114]. Satisfying silsesquioxane models have been reported [2, 114]. 

Zirconium complexes, 3, 363-440 acetylacetone, 2,372,377 ligand exchange reactions, 2, 381 rearrangement, 2, 383 alkyl... 

Mn(II) > Mg(II).270 It should be underlined that titanium and zirconium alkoxides are efficient catalysts for both stages of reaction. Lanthanide compounds such as 2,2/-bipyridyl, acetylacetonate, and o-formyl phenolate complexes of Eu(III), La(III), Sm(III), Er(III), and Tb(III) appear to be even more efficient than titanium alkoxides, Ca or Mn acetates, Sb203, and their mixtures.273 Moreover, PET produced with lanthanides has been reported to exhibit better thermal and hydrolytic stability as compared to PET synthesized with the conventional Ca acetate -Sb203 catalytic system.273... 

The kinetics of ligand exchange between [M(dik)4] (M = Zr or Hf dik = acac or tfacac) and the corresponding free /3-diketones have been studied by Adams and Larsen.233 [Zr(acac)4] exchanges ligands with a polystyrene resin functionalized with acetylacetonate groups to give a polymer-bound zirconium complex.234... 

The refractory carbides NbC and TaC and the nitride NbN, each with the sodium chloride structure, are also similar to the corresponding zirconium and hafnium compounds. Finally, it may be noted that the same group of complexing agents form complexes with Nb(V) and Ta(V) as with Zr(IV) and Hf(IV) (for example, fluoride, hydrogen peroxide, acetylacetone, and 1,2-dihydroxybenzene). 

Some seemingly simple zirconium salts are best regarded as essentially covalent molecules or as complexes examples are the carboxylates, Zr(0C0R)4, the tetrakis(acetylacetonate), the oxalate and the nitrate. Like its Ti analog, the last of these is made by heating the initial solid adduct of N205 and N204 obtained in the reaction... 

Intorre and Martell (237) have also studied the formation of mixed chelate species in which the zirconium 1 1 complex with the hexa-dentate chelating ligands, ethylenediaminetetraacetic acid, iV-hydroxy-ethylethylenediaminetriacetic acid, and m7 s-cyclohexanediaminetetra-acetic acid, are shown to take up one mole of the bidentate ligands, l,2-dihydroxybenzene-3,5-disulfonate l,8-dihydroxynaphthalene-3,6-disulfonate 8-hydroxyquinoline-5-sulfonate, and acetylacetone (except ZrHEDTA), to form 8-coordinate 1 1 1 species. At least for the zir-conium-EDTA-l,2-dihydroxybenzene-3,5-disulfonate species, there is evidence for dimerization (230). Additionally, the Zr EDTA complex reacts with one mole of the bidentate ligands, 5-sulfosalicyclic acid, alizarin sulfonate, citric acid, and lactic acid to form 1 1 1 complexes tartaric acid and pyrophosphate ions form complexes which could not be identified. The zirconium-nitriloacetic acid complex in the presence of two moles of oxalic acid or l,2-dihydroxybenzene-3,5-sulfonate also forms 1 1 1 complexes in solution. 

Zirconium bromide, anhydrous, 1 49 Zirconium complex compounds, nonelectrolytes, with acetylacetone, ZrCCsHjOili-lOHaO, 2 121 Zirconium oxybromide, formation of, from zirconium bromide, 1 51... 

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