STUDIES OF METAL-METAL BONDED AND LIGAND BRIDGED IVB METAL-TRANSITION METAL COMPLEXES.

摘要

A myriad of complexes containing the group IVB metals (Ti, Zr, and Hf) have been synthesized and spectroscopically studied. The complexes include cyanide-bridged polymers, {Cp(,2)M-NC-M'(CN)(,2)CN}(,2), where M=Ti,Zr,Hf and M'=Pt,Pd; sulfur-bridged polymers, {Cp(,2)M-(S(,2)M''S(,2))(,2)M'}(,n), where M''=Mo,W; metal-metal bonded complexes of varying structure, {Cp(,2)M-Fe(CO)(,4)}(,n); and oligomers containing both metal-metal bonds and iso-carbonyl linkages.;Reactions between IVB metallocene dihalides and the metal-sulfur complex dianions, (eg. Pt(WS(,4))(,2)('-2)), produce sulfur-bridged polymers. The synthesis of these materials represents the first hetero-trimetallic, organometallic polymers reported to date. The variations of electronic and structural arrangements at each metal center along with the postulated electron delocalization between metal centers of different oxidation states makes them fascinating materials. The synthesis, physical and chemical properties and the infrared spectra of the complexes are reported. The structure and bonding in these species is discussed. This study supports the notion that large complex anions can be used as nucleophiles in the synthesis of polymetallic macromolecules.;The reactions between IVB metallocene dihalides and iron tetracarbonyl dianion, Fe(CO)(,4)('-2), have resulted in the synthesis of three IVB metal-iron bonded species of the following composition: {Cp(,2)M-Fe(CO)(,4)}(,n), where M=Ti,Zr,Hf. The species are arguably dimeric and have been shown to undergo metal-metal bond cleavage by solvent species such as tetrahydrofuran. This result is an additional six metal-metal bonded complexes. Three contain an iso-carbonyl linkage, and three others exist in solution as the base associated manomeric species, {BnCp(,2)M-Fe(CO)(,4)}.(,).;The synthesis of these nine complexes has quadrupled the number of known metal-metal bonded complexes containing IVB metals. The Hf derivatives represent the first Hf-transition metal bonded species reported to date.;Group IVB metallocene dihalides, Cp(,2)MX(,2), have been shown to react with metal-cyanide complex anions, Pt(CN)(,4)('-2), to form cyanide-bridged polymers. The synthesis, physical and chemical properties, vibrational spectra (I.R. and Raman), X-ray powder patterns and magnetic susceptibility are reported. The I.R. and Raman spectra are analyzed and vibrational bands are assigned on the basis of a comparative study of the complexes reported in this thesis and related species reported in the literature. The structure and bonding of these species are discussed. The reactivities of these polymers with chemical agents such as Br(,2) and I(,2) are also discussed.;The synthesis, physical and chemical properties and vibrational spectra (I.R. and Raman) of these solids and solutions are reported. Vibrational modes are assigned to spectral bands on the basis of a comparative analysis of the complexes reported herein and of related species reported in the literature. NMR and mass spectra of the Zr derivatives are also reported.