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English: The aim of this study was to synthesize M(L,L’)4 type complexes of zirconium(IV) and hafnium(IV) using N,N’-diamine and O,O’-bidentate ligands. The synthesized complexes were characterized and a kinetic study of the formation of the respective complexes was performed. Characterization of the successfully synthesized complexes, tetrakis(thenoyltrifluoro-acetylacetone) zirconium(IV) monohydrate ([Zr(tta)4].H2O) and tetrakis(thenoyltrifluoroacetylacetonato) hafnium(IV) ([Hf(tta)4]) was done by infrared (IR), ultraviolet and visible spectroscopy (UV/Vis) and 1H and 19F nuclear magnetic resonance (NMR) spectroscopy. The structure of [Zr(tta)4]∙H2O was successfully characterized by single crystal X-ray diffraction while its hafnium counterpart was unsuccessful due to poor crystal quality. [Zr(tta)4].H2O crystallized in the orthorhombic space group Pca21 with Z = 4. The structure of [Zr(tta)4].H2O consists of a zirconium(IV) metal centre coordinated to eight oxygen atoms of four O,O’-bidentate ligands, with an average Zr—O bond distance of 2.18(7) Å and an average bite angle of 107(8)˚. Unlike common alternating CF3 groups with respect to the coordinating ligand, the CF3 groups of this structure were clustered in the plane of the molecule. In contrast to a similar structure the thenoyl rings of this structure were connected by a water molecule. In the kinetic investigations the formation reaction between zirconium(IV) and hafnium(IV) with the Na(tta) ligand at varying metal to ligand ratios were followed by 19F and 1H-NMR. Competition studies were also performed between the two metals and Na(tta). In both the studies the a general observation was made that the formation reaction consisted of two reactions: a fast first reaction and a slow second reaction. In the individual metal studies it was determined that the observed rate constants for the hafnium(IV) system were ~ 2 times faster than the zirconium(IV) system for the first fast reaction and ~ 7 times faster f, Afrikaans: Die doel van hierdie studie was om van M(L,L’)4 tipe komplekse van sirkonium(IV) en hafnium(IV) te sintetiseer met N,N’-diamien en O,O’-bidentate ligande. Die gesintetiseerde komplekse is gekarakteriseer en `n kinetiese studie rakende die vorming van die onderskeie komplekse is uitgevoer. Karakterisering van die gesintetiseerde komplekse, tetrakis(tenoïeltrifluoor-asetielasetoon) sirkonium(IV) monohidraat ([Zr(tta)4].H2O) en tetrakis(tenoïeltrifluoorasetielasetoon) hafnium(IV) ([Hf(tta)4]) is uitgevoer deur middel van infrarooi (IR), ultraviolet en sigbare spektroskopie (UV/Vis) en 1H en 19F kermagnetiese resonans (KMR) spektroskopie. Die struktuur van [Zr(tta)4].H2O is suksesvol deur enkelkristal X-straal diffraksie gekarakteriseer terwyl die karakterisering van die hafnium eweknie enkelkristal diffraksie met X-straal onsuksesvol was as gevolg van swak kristalkwaliteit. [Zr(tta)4].H2O Dit het gekristalliseer in die ortorombiese ruimtegroep Pca21 met Z = 4. Die [Zr(tta)4].H2O kompleks bestaan uit `n sirkonium(IV) metaalkern wat aan die agt suurstofatome van die vier O,O’-bidentate ligande gekoördineer is, met `n gemiddelde Zr—O bindingsafstand van 2.18(7) Å en `n gemiddelde bythoek van 107(8)˚. In teenstelling met algemene variasies in die CF3 groepe ten opsigte van die koördinerende ligand, groepeer die CF3 groepe van hierdie struktuur aan die dieselfde kant van die molekuul. Anders as in soortgelyke gepubliseerde strukture word die tenoïelringe van hierdie struktuur met `n water molekuul verbind. Vir die kinetiese ondersoek is die vormingsreaksie tussen sirkonium(IV) en hafnium(IV) met die Na(tta) ligand met wisselende metaal:ligand verhoudings deur middel van 19F en 1H KMR gevolg. Kompetisiestudies is uitgevoer tussen die twee metale en die Na(tta) ligand. In beide die studies is die algemene waarneming gemaak dat die vormingsreaksie uit twee reaksies bestaan: `n vinnige eerste reaksie en `n stadige tweede reaksie. In die individuele metaalstudies is v

English: The nuclear properties of rhenium (186/188Re) and technetium (99mTc) are used for their application as diagnostic and therapeutic radiopharmaceuticals. Researchers have shown a significant interest in rhenium and technetium tricarbonyl complexes of the form fac-[M(CO)3X(L,L’-Bid)]n where M = Tc(I) or Re(I), X = entering monodentate ligand and L-L’-Bid = different donor atom bidentate ligands, as potential diagnostic and therapeutic radiopharmaceuticals. These fac-[M(CO)3X(L,L’-Bid)]n type complexes are prepared from the starting synthons fac-[M(CO)3(Br3)]2- and fac-[M(CO)3(H2O)3]+ that was initially prepared by Alberto et al. in 1999. This starting synthon is a favourite all around for the synthesis of potential radiopharmaceuticals due to the easy preparation and the stability of fac-[M(CO)3(H2O)3]+ in aqueous solution in the pH range of 2 - 12 for several hours. The carbonyl ligands are tightly coordinated to the metal and form the stable fac-[M(CO)3]+ core. The three bromido or water ligands can be easily substituted by different functional groups such as thioethers, thiols, phosphines and amines. The aim of this study was to investigate the ability of the chosen donor atom N,O; S,S’; S,O bidentate and S,S’S” tridentate ligands to coordinate to the fac-[Re(CO)3]+ core. The results were compared to previous studies reported on N,O and O,O’ bidentate ligand systems to observe the variation in coordination behaviours. The chosen ligands include: 5-phenylazo-8-hydroxyquinoline, 5-(m-Tol)azo-8-hydroxyquinoline, 5-(2,3- diMephenyl)azo-8-hydroxyquinoline, 5-(2,6-diMe phenyl)azo-8-hydroxyquinoline, 5- (3,4-diMe phenyl)azo-8-hydroxyquinoline, methyl benzo[b]thiophene-2-carboxylate, benzothiophene-2-methanol, 2-mercaptophenol, 2-methoxythiophenol, 5-bromo-2,2`- bithiophene, 2,2′-bithiophene-5-carboxylic acid, benzene-1,2-dithiol, toluene-3,4- dithiol, and 2,2`-thiodiethanethiol. The synthesis of the complexes are described in Chapter 4 and characterized by IR, UV, Afrikaans: Die kern eienskappe van renium (186/188Re) en tegnesium (99mTc) word gebruik vir hulle toepassing in diagnostiese en terapeutiese radiofarmasie. Navorsers het reeds beduidende belangstelling getoon in renium en tegnesium trikarboniel komplekse van die vorm fas-[M(CO)3X(L,L’-Bid)]n, waar M = Tc(I) of Re(I), X = inkomende monodentate ligand en L-L’-Bid = verskillende skenkeratoom bidentate ligande, vir toepassing as potensiële diagnostiese en terapeutiese radiofarmaseutiese middels. Hierdie fas-[M(CO)3X(L,L’-Bid)]n tipe komplekse is voorberei vanaf fas-[M(CO)3(Br3)]2- en fas-[M(CO)3(H2O)3]+ wat aanvanklik deur Alberto et al. in 1999 berei is. Hierdie begin sinton is ʼn algemene gunsteling vir die sintese van potensiële radiofarmaseutiese middels danksy die maklike bereiding en stabiliteit van fas- [M(CO)3(H2O)3]+ in wateroplossing in ʼn pH reeks van 2 tot 12 vir verskeie ure. Die karboniel ligande is stewig aan die metaal gekoördineer en vorm die stabiele fas- [M(CO)3]+ kern. Die drie bromido of water ligande kan maklik deur verskillende funksionele groepe soos tioësters, tiole, fosfiene en amiene gesubstitueer word. Die doel van hierdie studie was om die vermoë van die gekose skenkeratoom N,O; S,S’; S,O bidentate en S,S’S” tridentate ligande aan die fas-[Re(CO)3]+ kern te koördineer te ondersoek. Die resultate is met vorige studies rakende N,O en O,O’ bidentate ligandstelsels vergelyk ten einde die variasie in koördinasiegedrag waar te neem. Die gekose ligande sluit in: 5-fenielaso-8-hidroksiekinolien, 5-(m-Tol)aso-8- hidroksiekinolien, 5-(2,3-diMe-feniel)aso-8-hidroksiekinolien, 5-(2,6-diMe-feniel)aso-8- hidroksiekinolien, 5-(3,4-diMe-feniel)aso-8-hidroksiekinolien, metiel benso[b]tiofeen-2- karboksilaat, bensotiofeen-2-metanol, 2-merkaptofenol, 2-metoksietiofenol (BSOFCH), 5-bromo-2,2`-bitiofeen, 2,2′-bitiofeen-5-karboksielsuur, benseen-1,2-ditiol, tolueen-3,4-ditiol (m-TolBSFH2) en 2,2`-tiodietaantiol (TSH2). Die sintese van die komplekse word in Hoofstuk

Manganese has largely been used as a catalyst in epoxidation of olefins and the selective oxidation of unactivated C-H bonds in alkanes. Another major use of manganese is in water oxidizing catalysis, where manganese compounds are used in the production of hydrogen by water splitting. By looking at the manganese triad, a lot of radiopharmaceutical studies have been performed with Technetium. 99mTc is the radionuclide of choice since it has the ideal properties necessary for potential radiopharmaceuticals. Rhenium has been used as model for technetium radiopharmaceuticals and 188Re and 186Re have proved their use in bone metastases. Manganese has not been used in radiopharmaceuticals as it is somewhat toxic to the body. Some studies have been performed on tumor suppression using MnSOD, a mitochondrial enzyme. Very little work has been done on manganese coordination chemistry especially in terms of tricarbonyl aqua complexes. So far about 5 manganese tricarbonyl aqua complexes have been reported on the CSD. In this study, a comparison of manganese (I) and rhenium (I) tricarbonyl complexes is made. Rhenium (I) tricarbonyl aqua complexes have been synthesized by Kemp and Schutte et al. using N,N’-, N,O- and O,O’- bidentate ligands. The chosen N;N’- bidentate ligands are 2,2’-bipyridyl (Bipy) and 1,10-phenanthroline (Phen), N,Obidentate ligands are quinoline-2,4-dicarboxylic acid (2,4-Quin) and picolinic acid (Pico) and finally the O,O’-bidentate ligands chosen were 3-hydroxyflvone (Flav) and tropolone (Trop). In this study, the same N,N’- and N,O-bidentate ligand systems were used as well as 3-hydroxyflavone as O,O’-bidentate ligand in order to successfully compare these two metal cores. The synthesis of all the complexes has been reported in Chapter 3 and these were characterized by UV/vis, 13C NMR, 1H NMR and IR. Only two of the complexes were characterized by X-ray diffraction; fac-[Mn(CO)3(Bipy)(H2O)][CF3SO3] and fac- [Mn(CO)3(Phen)(H2O)][CF3SO3]. These monoclinic c