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The bridged (14)annulene dimethyldihydropyrene (1) aromatic ring current probe, was used to examine the bond localization effects of tricarbonylchromiumbenzene (37) hexamethylbenzenerutheniumbenzene (38), tricarbonylmanganesecyclopentadienyl (4) and pentamethylcyclopentadienylrutheniumcyclopentadienyl (39), when fused to the annulene. The H NMR spectra for each compound was given detailed analysis regarding the ring current shielding of the internal methyl protons and external protons. Diamagnetic anisotropy effects were removed using the McGlinchey equation.

The role of calix(4)arene as a supporting ligand compared to cyclopentadienyl and phenoxo anion is emphasized through the micratory insertion reaction of carbon monoxide and isocyanides, in the Zr-C bond. A kinetically and structurally defined stewise insertion process is reported. The reactions occur via metal-assisted C-C bond formation, resulting in a variety of carbon-metal-bonded fragmenets. Extended Huckel calculations were also performed.

The full synthesis and chemical behaviour of the Zr-C bond functionalities bonded to the Osub4 skeleton is reported. The approach is based on the synthesis and organometallic functionalization of (calix(4)-(OMe)(O)sub3ZrC1)sub2 and (calix(4)-(OMe)sub2(O)sub2ZrC1sub2), giving rise to two classes of derivatives linked by the based-induced demethylation of a methoxy group. The main differences between the (Osub4ZR)super2+, (Osub4Zr)+ and (Cpsub2Zr)super2 fragements are emphasized.

Trovacenyl carboxylic acid (etasuper7-Csub7Hsub7)V(etasuper5-Csub5Hsub4COOH) (2) and its anhydride was afforded through lithiation of trovacene ((etasuper7-tropylium)vanadium(etasuper5-cyclopentadienyl)) (1) and appropriate subsequent reactions. The dimeric hydrogen bonded structure of 2 was found to prevail in aprotic, nonpolar solvents, giving rise to a biradical EPR spectrum from which electron exchange coupling constant J = -0.011cm-1 was determined through computer simulation.

Organolanthanide and group 3 organometallic complexes have uses as catalysts in organic synthesis. The ability to predict the chemoselectivity of the reaction prior to preparation of the starting material is of major concern. Substituion patterns will depend wholly on catalyst reactivity, and it has been demonstrated that reactivity relies on the steric environment of the alkene or alkyne. Using the catalysts Cp(sub2)YMe.THF and (CpTMS(sub2)YMe)(sub2), alkynes and alkenes exhibited increased reaction rate due to electronic effects.

Several synthetic methods for polyquinane natural products offer quick and efficient access to polyquinanes, but can lack generality. A general, regiospecific, tandem reaction method, resulting in highly substituted linearly-fused polyquinanes from dialkyl squarates and organometallic reagents, has been developed. It enables functionality to be strategically placed at most positions of the polyquinane skeleton. A variant of the method, leads to bicyclo(6.3.0)undecadienones.

The use of monoboranes in the synthesis of multinuclear metallaboranes has been pursued. Monocyclopentadienylmetal chloride dimers have recently been explored, as a possible general source of metallaboranes, and have been found to be a good leaving group. BH(sub3).THF has a dual role, transporting chlorine as BH(sub2)C1 and condensing on a dimer framework, forming B-B and B-M bonds. The approach gives new metallaboranes of Co, Cr, Mo and Ta, enabling the development of their derivative chemistry.

The general formula (RLi.LiOR) for mixed complexes is well known, with mixed alkyllithium/lithium alkoxide systems receiving much attention. The decomposition of tert-butyllithium/lithium tert-butoxide complexes in cyclopentane solution was found to result in a hydrocarbon soluble form of LiH. Both photochemical and thermal decomposition identified two different LiH-containing aggregates.

Reports have shown that boratabenzene ligands are useful substitutes for cyclopentadienyl (Cp) ligands and allow tuning of the electron density and reactivity of electrophilic metals. The synthesis and reactivity of the ethoxyboratabenzene complex (Csub5Hsub5B-OEt)sub2ZrC1sub2 (4) is reported and it is shown that (4)/methylaluminoxane acts to prepare 1-alkenes from ethylene, widening the scope of metallocene-like catalysts into new manufacturing methods for industrially significant molecules.

An analysis of the synthesis and characterization of (Et4N)(W(CO)5OH) and (PPN)(W(CO)5HCo3) elucidates their reactivity with carbondioxide and establishes the molecular structure of bicarbonate complexes. IR and C NMR spectroscopies help characterize (PPN)(W(Co)5HCO3), synthesized from W(CO)5 (acetone) and PPN (HCO3), in efforts to isolate the bicarbonate complex.

A study of the organometallic chemistry of thiophene discovered that the reaction of benzo(3,4-c)thiophene with photolytically produced (Cr(thf)(CO)5) at room temperature yields (Cr(C8H6S)(CO)3) (2) up to 62%. X-ray crystallographic analysis of 2 was conducted to differentiate between the probable eta6-coordination of the benzo ring and the eta5-coordination of the thiophene ring. The benzo ring is asymmetrically eta6-coordinated to chromium, having a marginally longer Cr-C bond to the carbon atoms that the thiophene and benzo rings have in common.