The contents of this thesis fall naturally into four sections which form the subjects of Chapter 2-5- Chapter 1 comprises a general introduction and literature survey of the most relevant areas. In Chapter 2 the preparation and characterisation of a series of carbonylmetallate anions fac-[MX(CO)3L2]- where M = Mo or W, X = Cl, Br or I and L2 = 1, 10-phenanthroline or 2, 2'-bipyridine from the corresponding cis- [M(CO)4L2] complexes is described. Solution infrared studies indicated that these complexes do not isomerise to the mer-isomers as suggested previously, but are solvolysed in acetonitrile with the formation of fac-[M(CO)3L2(MeCN)]. Reaction of the anions with various allyl halides resulted in high yields of the n3-allyl complexes [(n3-RC3H4)MX(CO)2L2]. The significance of these observations for the mechanism of the allyl oxidative-addition reaction is discussed. Reactions between Mn(CO)5X and Et4NX (X = Cl, Br) in boiling chloroform and between Re(CO)5X and Et4 NK (X = Cl, Br, I) in boiling decalin are described in Chapter 3. The final products are the compounds Et4N[M2(CO)6(?-X)3]. Vibrational spectroscopic results indicate that the anions possess confacial bi-octahedral geometry with three bridging halogen atoms. The anions did not react with allyl halides to give n3-allyl derivatives. Details of the preparation of [(n1-C3H5)Re(CO)5] from [Re(CO)5]- and its photo-decarbonylation to [(n3-C3H5)Re(CO)4] are presented in Chapter 4. Both allyl complexes have been characterised using 1H NMR, mass spectrometry and particularly liquid-phase infrared and Raman spectroscopies. Although the vibrations of the Re(CO)5 unit in the n1-allyl compound can be assigned in terms of C4v symmetry, such a local symmetry approximation has been found to be invalid for the n3-allyl compound whose vibrational spectrum requires discussion in terms of the overall Cs symmetry. The n1- and n3- allyl internal modes are discussed in terms of Cs symmetry. For comparative purposes the methyl derivatives [MeRe(CO)5] (Me = 12CH3, 13CH3, 12CD3) have also been synthesised and their mass and vibrational spectra studied. In Chapter 5 some carbonyl substitution reactions of [(n3-C3H5)M(CO)4] (M = Mn, Re) are reported. The use of thermal or photolytic methods has allowed the synthesis of the complexes [(n3-C3H5)M(CO)3L], (M = Mn, L = PPh3, AsPh3, PCy3, PBun3, PMePh2); M = Re, L = PPh3) and [(n3-C3H5)M(CO)2L2], (M = Mn, L = PMePh2, P(OMe)3, P(OEt)3, 1/2Ph2PCH2PPh2; M = Re, L = PPh3). These complexes are considered to possess pseudo-octahedral structures, the carbonyl ligands being facial in the tricarbonyls and cis in the dicarbonyls. The 1H NMR spectra are characteristic of symmetrical n3-allyl species and show strong 1H-31P coupling. Mass spectra have been obtained and fragmentation pathways suggested mainly on the basis of observed metastable peaks. A single crystal X-ray structure determination has been carried out on the complex [(n3-C3H5)Mn(CO)2{P(OMe)3}2]. 1742 independent reflections above background have been collected and refined to R = 0.059. Considering the n3-allyl group to occupy two coordination sites, the metal has a distorted octahedral environment being bonded to two mutually trans- phosphorus atoms 2.175(5), 2.219(5) A, two cis- carbonyl groups 1.75(2), 1.83(2) A and a n3-allyl ligand with Mn-C 2.223(17), 2.114(14), 2.229(13) A. Appendices 1 - 5 contain details of experimental methods, starting materials, group theory, secular equations and computer programmes used in this work. Appendix 6 lists the structure factors and thermal parameters associated with the crystal structure determination.

The thesis is divided into seven chapters. The first reviews methods of preparation of tricarbonyliron complexes of organic molecules, with particular emphasis on their synthesis in enantiomerically enriched form. Chapter two describes the use of these complexes in controlling the stereochemical outcome of reactions carried out on functional groups appended to the organic ligand. The third chapter describes methods of releasing the organic ligand in a stereoselective manner. Chapter four outlines an example of 1,5-induction of chirality in the diastereoselective allylation of ketone groups appended to the allyl ligand of π-allyltricarbonyliron lactone complexes. Attempts at manipulating incorporated side-chain functionality in these complexes are discussed in Chapter five. The Mukaiyama aldol reaction provides a powerful tool for stereoselective C-C bond formation. The use of π-allyltricarbonyliron lactone complexes bearing methyl ketone-derived silyl enol ether functionality in an asymmetric Mukaiyama aldol reaction is discussed in Chapter six. This reaction provides a novel example of 1,7-induction of chirality.

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Studies have been made on the formation of oxide solid solutions, and on their structural and electronic properties. Three different oxide systems have been investigated: CoO-MgO, MnO-CaO and CuIn2O4-CdIn2O4 CoO-MgO (0-10 mo1 % Co) has been prepared in low, medium and high surface area (LSA, MSA and HSA) forms. The lattice parameter, ao, was determined by X-ray diffraction (XRD) for LSA and MSA specimens, and by electron diffraction for HSA specimens where severe line broadening precludes accurate determination of ao by XRD. The increase in ao with [Co] was found to be identical in all cases, which implies that solid solution is maintained even at very small particle size (D < 500 A). However, reflectance spectra of MSA (D = 500 - 1.000 A) and HSA (D = 200 - 500 A) oxides show that some Co in the surface layers of finely-divided outgassed CoO-MgO is not in octahedral coordination. MnO-CaO, prepared by heating coprecipitated carbonates at 1273 K in vacuo, has been shown to form a solid solution over the whole composition range in spite of the large difference (22%) in cation radius. ESR studies showed the site symmetry of Mn2+ to be accurately cubic. The onset of magnetic interactions between manganese ions takes place when [Mn] = 1% for the dipole interaction and when [Mn] = 3% for the exchange interaction. By co-addition of Na+ ions small amounts of Mn3+ can be incorporated in solid solution in CaO. CuIn2O4 specimens have been prepared by solid state reaction between CuO, CdO and In2O3 at three different temperatures (1173, 1223 and 1323 K) and, by X-ray analysis, solubility limits have been found at 2.4, 2.9 and 5.2 mol % Cu respectively. A study has also been made on the crystal structure of CdIn2O4.

This thesis describes the preparation and characterisation of various types of Group VII metal carbonyl complexes. The first chapter outlines the experimental techniques used in the work. The second chapter reviews the known types of cationic metal carbonyls and discusses the syntheses of cationic manganese and rhenium carbonyl complexes via substitution reactions of [M(CO)3(NCMe)3]+ClO4-. Substitution products isolated include tricarbonyl complexes of the types [M(CO)3(terdentate)]+, [M(CO)3(bidentate) (NCMe)]+, [M(CO)3 (monodentate) (NCMe)2]+, [M(CO)3(monodentate)2(NCMe)]+ and [M(CO)3(monodentate)3]+ as well as the dicarbonyl complex [Mn(CO)2(Ph3P)2(NCMe)2]+ClO4-. Cotton-Kraihanzel carbonyl stretching parameters for several of the complexes have been calculated and their value assessed. The third chapter concerns the photochemical substitution of carbonyl groups from (n5-MeC5H4)Mn(CO)3 by various bidentate ligands (arphos, dpae, dpam, dppa, dppe and dppm). Products of the types (n5-MeC5H4)Mn(CO) (L-L) with chelating ligands and [(n5-MeC5H4)Mn(CO)2]2(L-L) with bridging ligands were isolated. (n5-MeC5H4)Mn(CO)2PPh3 was similarly prepared. Considerable emphasis was placed upon the interpretation of the mass spectral fragmentation patterns of these products. The fourth chapter deals with the 31P nuclear magnetic resonance spectra of a number of the cationic and methylcyclo-pentadienyl complexes described in chapters 2 and 3. The anomalous 31P chemical shift behaviour of ditertiary phosphine chelate complexes previously noted for Group VI and Group VIII metals was also evident in the Group VII compounds. This behaviour can be used to distinguish between bidentate chelating and bidentate bridging coordination modes for ditertiary phosphine ligands. The final chapter describes some halogenation reactions of Group VI and Group VII transition metal carbonyl complexes. Part A of this chapter deals exclusively with products containing coordinated acetonitrile. A new convenient route to the preparations of MoC14(CH3CN)2, MoBr3(CH3CN)3, WX4(CH3CN)2 (X = C1, Br), and ReX4(CH3CN)2 (X = C1, Br) has been established. Part B discusses some halogenations of rhenium carbonyl complexes of the type fac-[Re(CO)3XL2]. Using mild conditions some seven-coordinate rhenium(III) complexes of the type Re(CO)2X3L2 have been isolated. More extreme reaction conditions afford six-coordinate rhenium(IV) halo-complexes.

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In order for luminescent lanthanide complexes to be used in fluoroimmunoassays, a number of criteria must be adhered to, such as high quantum yield, high stability in aqueous media and insensitivity to the surrounding environment. In this thesis, a number of new ligand systems, designed with regard to achieving novel sensitising ligands of europium and terbium for use in cellular assays are discussed. A new ligand based upon a macrocyclic polyaminocarboxylate incorporating a single bipyridine chromophore and its complexes of europium and terbium are reported. Luminescence properties of both complexes are very good, with the terbium analogue displaying more complex behaviour, which suggest a back energy transfer mechanism from the emissive metal centre to the bipyridine triplet. The development of a different ligand incorporating the bipyridine chromophore as the binding groups based on a macrocyclic backbone are also reported. Simple intramolecular europium and terbium complexes of salicylaldehyde and ohydroxybenzophenone were prepared and their photophysical properties recorded. These chelates showed poor stability in solution which led to the investigation of azacrown appended version of these ligands with the aim to improve stability. Europium chelates of these sensitisers displayed poor emissive properties at room temperature postulated to be due to a ligand to metal charge transfer deactivation mechanism. Finally, with the aim of developing charge neutral, fat-soluble luminescent lanthanide complexes capable of cell loading, donors of mixed pyrido-phenol sensitisers were developed. The luminescent properties were found to be poor for the europium complex due to ligand to metal charge transfer. Terbium complexes of these ligands showed sensitivity towards oxygen and temperature, indicating the presence of back energy transfer from the metal centre to the aryl triplet. Complexes of 8- hydroxyquinoline with europium are also reported.

The work detailed in this thesis describes density functional (DF) calculations that were performed to investigate the possible role of metallophosphoranes in the reactions of palladium-phosphine complexes. A study was conducted on X/R exchange in [M(Cl)X(PH3)(PR3)] (X = F, OH, NH2, Me, Ph, Cl; R = H, Me, F; M = Ni, Pd, Pt), to see how metallophosphorane formation, followed by R-transfer, was affected by varying the X ligand, nature of the accepting phosphine (PR3) or the metal centre. Metallophosphorane formation was easiest with the small, electronegative X ligands such as F and OH and was promoted by electron-withdrawing R substituents on the accepting phosphine. When the metal centre was varied, the trend for the activation barriers was Ni < Pd < Pt. Subsequent R-transfer was always more facile than metallophosphorane formation. The mechanism of disproportionation of [Pd(Cl)OH(PPh3)2] was studied using DF calculations on the model system [Pd(Cl)OH(PH3)2] and hybrid DF:HF methods on the full experimental complex. In the small model a reaction profile was found via a metallophosphorane intermediate formed via a transition state at 28.3 kcal/mol (from the trans reactant) or a transition state at 21.8 kcal/mol (from the cis reactant). A similar mechanism was found with the full experimental complex (highpoint 27.5 kcal/mol) but a more accessible route was located via a zwitterion intermediate, [PdPPh3Cl]-[P(OH)Ph3]+ (highpoint 26.7 kcal/mol). Possible mechanisms for experimentally-observed Ph/Ph exchange in trans- [PdX(Ph)(PPh3)2] (X = Cl, Br, I) and R/Ph exchange in trans-[PdI(R)(PPh3)2] (R = Me, CH2CF3) were studied using DF:HF calculations. For Ph/Ph exchange, the most accessible pathway involved pre-dissociation of a phosphine, followed by intermolecular attack of the palladium-bound phenyl on the remaining phosphorus. The lowest activation barriers were seen when X = I. The equivalent mechanism was also the most accessible for Me/Ph exchange, although the analogous mechanism without pre-dissociation of phosphine was very competitive. R/Ph exchange was computed to be considerably less accessible when R = CH2CF3 than when R = Me.