This Thesis describes the synthesis and characterisation of half-sandwich complexes supported by κ¹-amidinate and κ¹-guanidinate ligands as well as the cationic species produced on activation. The chemistry of the cationic species is detailed and DFT studies which have also been carried out to elucidate the bonding in relevant complexes are also presented.

This thesis is a case study of coordination policies and practices in child protection services. The study is an exploratory, descriptive account of the processes and outputs of interagency coordination rather than a hypothesis-testing study or an evaluation of the outcomes of coordination. It is based on empirical research undertaken in two research sites in the north of England. The principal data sources used in the research were: an analysis of the social services departmental case records relating to a sample of 48 children on child protection registers for physical or sexual abuse; interviews with 90 professionals (social workers, teachers, community nurses, police officers, doctors and others), drawn from a sub-sample of the 48 cases; a questionnaire issued to those interviewed and selected others, completed by 81 respondents; and analysis of central government guidance, local interagency procedures and other documents. In Chapter One of the thesis, selected topics in the literature on interagency coordination and the policy background to the study are reviewed. The research methods used and the characteristics of the case sample and the interview and questionnaire respondents are presented in Chapter Two. The principal research findings are presented in Chapters Three to Eleven covering three main topics: i) interagency coordination in the key phases of a case career (namely referral, initial investigation, medical assessment, case conferences, child protection plans and intervention, monitoring and review) ii) an examination of local interagency procedures and the role of Area Child Protection Committees and iii) the perceptions and experiences of respondents concerning interagency work. The thesis concludes that there is a high degree of routinised coordination with a relatively clear division of labour in child protection services; that coordination involves principally the exchange of information, arranging for the sequential and separate performance of key tasks and some limited shared decision-making but that there is little joint hands-on collaboration; that interagency activity peaks in the early phases of the construction of a case and diminishes thereafter; that the implementation of policy guidance may be seen as relatively successful and that there is some support for the idea that interagency coordination strategies tend towards conservatism.

The current study aimed to discover whether, and to what extent, children and adolescents at risk of Developmental Coordination Disorder (DCD) perceive themselves as lacking competence, control, social support and self-worth. In addition, the study aimed to discover whether, and to what extent, children and adolescents at risk of DCD experience more trait and state anxiety than their peers. Fifty-eight children aged 8- to 10-years identified as being at risk of DCD were matched with 58 control children on age and gender, and fifty-one adolescents aged 12- to 14-years at risk of DCD group were matched with 51 control adolescents. Children and adolescent at risk of DCD were compared to the control group on measures of perceived competence, perceived control, perceived social support, self-worth and anxiety. Multivariate Analysis of Variance revealed that children and adolescents at risk of DCD performed significantly more poorly than the control group on measures of perceived competence, perceived control, perceived social support, self-worth and state and trait anxiety. In addition, significant differences were found on some measures for age, whilst only the self-perception profile differentiated gender.Based on the assumption that children and adolescents with poor motor coordination do have negative views of self and experience relatively high levels of anxiety, a second aim of the study was to test an aetiological model of anxiety. Harters (1987) model of the determinants of self-worth provided a sound theoretical basis for investigating the relationships between self-perceptions and affect. Self-perception, according to Harter, precedes emotional and behavioural outcomes. A series of path analyses conducted separately for each group revealed differences in the pattern of interrelationships between the dependent variables for children and adolescents at risk of DCD ++ / and the control group. The salient findings were that for both groups physical appearance was an important and consistent determinant of self-worth. Few significant pathways were identified for those in the DCD group limiting the conclusions that could be drawn from this study.Overall, given the negative consequences of poor motor coordination identified in the current study it would seem imperative that early assessment and diagnosis of DCD be introduced into the school system.

The chemistry and physical properties of actinide complexes has become increasingly significant and relevant since the dawn of the nuclear age. In addition to increasing the potency of nuclear power and the safety and disposal of its subsequent waste products, exploration of the chemistry of actinide complexes provides a fascinating insight into the increased complexity and divergence of reactivity of these complexes when compared to transition metal complexes. Chapter One provides a brief introduction to the chemistry of actinides and in particular, the major focus of this work, of thorium. This is followed by a survey of examples of rare examples of thorium complexes with a formal oxidation state other than Th (IV). Following this is a review of selected examples of thorium (IV) complexes exhibiting unusual reactivity surveying thorium hydride and alkyl complexes initially. This progresses into reviewing the chemistry of thorium complexes containing multiple bonds to non-metal atoms, beginning with carbon atoms and then progressing to atoms in the chalcogen and pnictogen groups. The introduction finishes with an investigation into the properties of the terphenolate ligands used in this study, including examples of unusual complexes that they have been shown to stabilise. In Chapter Two, an exploration into the catalytic activity of fairly simple actinide amide catalysts, N”2Th (IV) {k2-N(SiMe3)SiMe2CH2, N”2U (IV) {k2-N(SiMe3)SiMe2CH2} and UN”3, upon terminal acetylenes is presented. The chapter begins with a brief introduction summarising the previous reactivity observed in the catalysis of terminal acetylenes, with particular focus on actinide-based catalyst mediated reactions. The catalytic results on a variety of terminal acetylenes with different steric and electronic properties is then reported upon. It is found that high conversions and selectivities can be achieved upon optimisation of the catalytic process. It was also found that the different catalysts and substrates favoured different products, with selective oligomerisation and cyclotrimerisation reactions observed. The differing reactivities lend support to the role of f-electrons upon the catalytic route of the reaction. Conclusions are discussed at the end of the chapter. In Chapter Three, the synthesis and characterisation of heteroleptic terphenolate thorium chloride complexes and their subsequent reactivity was investigated. The synthesis and characterisation of ThCl2(OTerMes)2DME and ThCl2(OTerMes)2(H2O)3 are initially described. The reactivity of these complexes favoured transmetallation of the terphenolate ligands, with the complexes; [Li(OTerMes)THF]2, [Li(OTerMes)]2THF, μ3- (TerMesO)μ3-(CH2SiMe3)3Li4, LiAlH2(OTerMes)2, [(THF)K(OTerMes)]2, MgCl(OTerMes)(THF)2, MgBr(OTerMes)(THF)2 and Fe(OTerMes)2(py)2 synthesised and characterised from reactions attempting to transform the ancillary chlorido-ligands. The reactivity of ThCl2(OTerMes)2DME was found to not be solely transmetallation of the terphenolate ligands as elucidated by the synthesis and characterisation of [Th(OTerMes)2(Cl)2(4,4’- bipyridyl)1.5]∞ and [MgTh2μ2-Cl2μ3-Cl(OTerMes)2(C4H7)2μ-η3:η3(C4H7)H]. The synthesis of [MgTh2μ2-Cl2μ3-Cl(OTerMes)2(C4H7)2μ-η3:η3(C4H7)H] was found to proceed via a reductive elimination route with concomitant formation of a terphenolate transmetallation product Mg(OTerMes)2(THF)2. The formation of[Th(OTerMes)2(Cl)2(4,4’- bipyridyl)1.5]∞ was achieved via reaction with the Lewis base 4-4’ bipyridine. Reactions attempting to form heteroleptic uranium terphenolate complexes were also detailed. Conclusions are discussed at the end of the chapter. In Chapter Four, the synthesis and characterisation of heteroleptic terphenolate thorium borohydride complexes and their subsequent reactivity was investigated. It was found that the conversion of ThCl2(OTerMes)2DME to Th(BH4)2(OTerMes)2DME proceeded smoothly using a precedented reaction route. In contrast to ThCl2(OTerMes)2DME, reaction with a Lewis acid was found to result in abstraction of the solvating DME molecule, resulting in the synthesis and characterisation of Th(BH4)2(OTerMes)2. In similarity to ThCl2(OTerMes)2DME, Th(BH4)2(OTerMes)2DME was found to react with a Lewis base (4-4’ bipyridine) to form Th(BH4)2(OTerMes)2(4,4’ bipyridine)∞. However, despite the increased robustness and versatility of the borohydride complexes, transmetallation of the terphenolate complexes remained an issue as shown by the synthesis and characterisation of Mg(OTerMes)((μ-H)3BH)THF)2. Th(BH4)2(OTerMes)2 was found to be able to facilitate small molecule activation in a variety of substrates, encompassing CO, CO2 and CS2 amongst others. In most cases this small molecule activation favoured the formation of BMe3, with the concomitant formation of HB(OTerMes)2 in the case of CO2 and CS2. Attempts at catalysis of isonitriles and terminal acetylenes by Th(BH4)2(OTerMes)2 are presented with mixed results. Conclusions are discussed at the end of the chapter. In Chapter Five, investigations into the effects of changing the donor atom of the terphenyl moiety were probed. The chapter began by examining the differing properties of a phosphorous atom acting as a ligating atom, as opposed to the oxygen atom seen in Chapters Three and Four. The chapter continued by detailing the result of reactions attempting to synthesise and characterise terphenyl phosphino-actinide complexes. It was found that in the case of actinides with easily accessible lower oxidation states, i.e. U (IV), that reductive elimination was favoured, culminating in the isolation of (TerMesPH)2. Following this result attempts were made to modify the ligand system in an attempt to divert the reaction away from this product, in the hope of isolating a phosphino-actinide complex. Reactions attempting to ligate the terphenyl moiety via the aryl α-carbon to thorium were also detailed, resulting in radicular degeneration and the isolation of nBuTerTrip and ClTerTrip. Conclusions are discussed at the end of the chapter. Experimental and characterising data are provided in Chapter Six.

Visual-motor integration, visual perception and motor co-ordination contribute to successful academic, school and career life. Literature also indicates that delays in the skills in above mentioned abilities could lead to delays in the mastering of object control skills. Furthermore, due to the developing needs of South Africa, there is a range of socio-economic challenges, and the effects on the above mentioned skills seem to lack development. Due to the possible effect that visual skills can have on academic performance, it seems important to further investigate the effect it may have on sport skills as well. The aim of this study was firstly, to determine the effect of gender differences and school types associated with different socio-economic conditions on the visual-motor integration, visual perception and motor co-ordination abilities of Grade 1 boys and girls in the North West Province of South Africa. Secondly, the study aimed to determine the relationship between visual-motor integration, visual perception, motor co-ordination and object control skills of Grade 1-learners in the North West Province of South Africa. For the purpose of the first objective 816 participants (419 boys and 397 girls) were evaluated and for the second objective, 806 participants (413 boys and 393 girls) were evaluated. The test instrument used to determine the level of the participants’ visual-motor skills was the Developmental Test of Visual-Motor Integration – 4th ed. (VMI-4) which consisted of the visual- motor integration test and two subtests which included visual perception and motor co- ordination. The children’s object-control skills were tested with the Test of Gross Motor Development – 2 (TGMD-2) which is designed to test the gross motor functioning of children from 3 to 10 years old. The STATISTICA software package (StatSoft, 2013) was used to analyse data. Data was analysed by means of descriptive statistics as well as a variation analyses (ANOVA). ANOVA was used to determine the interaction effect between gender and/or socio-economic status and visual-motor integration, visual perception and motor co-ordination. Independent t-testing was used to determine the effect of gender differences and socio-economic status in visual-motor integration, visual perception and motor co-ordination. Effect sizes (d) were used to calculate practical significance of differences. Two-way frequency tables were used to compare the classifications of the different school quintiles (Quintile 1-3 = schools associated with low socio-economic status and Quintile 4-5 = schools associated with high socio-economic status) among the VMI-4-classes. The Pearson Chi-square was used to indicate the significance of the differences and the level of statistical significance was set at p≤0.05. Furthermore a Spearman rank order correlation was used to determine the correlations among visual-motor integration, visual perception, motor co-ordination, striking a stationary ball, stationary dribble, catch, kick, underhand rolling and overhand throw, and an object control total. The results revealed that gender had no significant effect on visual-motor integration, visual perception and motor co-ordination within the respective school types associated with different socio-economic conditions. Although there were no significant differences between the boys and girls, statistically significant higher mean scores were found in school types associated with higher socio-economic status (Quintile 4 and 5) with regard to visual-motor integration, visual perception and motor co-ordination. The object control skills total had small and medium correlations with visual- motor integration, visual perception and motor co-ordination. Visual perception had the highest correlation with the object control skills total. These results contribute to our understanding of the influence that visual-motor integration, visual perception and motor co-ordination have on sport skills and more specifically ball sport skills. This knowledge enables researchers to better address problems which present in early years with regard to visual skills, as well as the negative impact which low socio-economic circumstances have on these skills in order to improve academic and sport skills later. / MA (Child Kinetics), North-West University, Potchefstroom Campus, 2015

Visual-motor integration, visual perception and motor co-ordination contribute to successful academic, school and career life. Literature also indicates that delays in the skills in above mentioned abilities could lead to delays in the mastering of object control skills. Furthermore, due to the developing needs of South Africa, there is a range of socio-economic challenges, and the effects on the above mentioned skills seem to lack development. Due to the possible effect that visual skills can have on academic performance, it seems important to further investigate the effect it may have on sport skills as well. The aim of this study was firstly, to determine the effect of gender differences and school types associated with different socio-economic conditions on the visual-motor integration, visual perception and motor co-ordination abilities of Grade 1 boys and girls in the North West Province of South Africa. Secondly, the study aimed to determine the relationship between visual-motor integration, visual perception, motor co-ordination and object control skills of Grade 1-learners in the North West Province of South Africa. For the purpose of the first objective 816 participants (419 boys and 397 girls) were evaluated and for the second objective, 806 participants (413 boys and 393 girls) were evaluated. The test instrument used to determine the level of the participants’ visual-motor skills was the Developmental Test of Visual-Motor Integration – 4th ed. (VMI-4) which consisted of the visual- motor integration test and two subtests which included visual perception and motor co- ordination. The children’s object-control skills were tested with the Test of Gross Motor Development – 2 (TGMD-2) which is designed to test the gross motor functioning of children from 3 to 10 years old. The STATISTICA software package (StatSoft, 2013) was used to analyse data. Data was analysed by means of descriptive statistics as well as a variation analyses (ANOVA). ANOVA was used to determine the interaction effect between gender and/or socio-economic status and visual-motor integration, visual perception and motor co-ordination. Independent t-testing was used to determine the effect of gender differences and socio-economic status in visual-motor integration, visual perception and motor co-ordination. Effect sizes (d) were used to calculate practical significance of differences. Two-way frequency tables were used to compare the classifications of the different school quintiles (Quintile 1-3 = schools associated with low socio-economic status and Quintile 4-5 = schools associated with high socio-economic status) among the VMI-4-classes. The Pearson Chi-square was used to indicate the significance of the differences and the level of statistical significance was set at p≤0.05. Furthermore a Spearman rank order correlation was used to determine the correlations among visual-motor integration, visual perception, motor co-ordination, striking a stationary ball, stationary dribble, catch, kick, underhand rolling and overhand throw, and an object control total. The results revealed that gender had no significant effect on visual-motor integration, visual perception and motor co-ordination within the respective school types associated with different socio-economic conditions. Although there were no significant differences between the boys and girls, statistically significant higher mean scores were found in school types associated with higher socio-economic status (Quintile 4 and 5) with regard to visual-motor integration, visual perception and motor co-ordination. The object control skills total had small and medium correlations with visual- motor integration, visual perception and motor co-ordination. Visual perception had the highest correlation with the object control skills total. These results contribute to our understanding of the influence that visual-motor integration, visual perception and motor co-ordination have on sport skills and more specifically ball sport skills. This knowledge enables researchers to better address problems which present in early years with regard to visual skills, as well as the negative impact which low socio-economic circumstances have on these skills in order to improve academic and sport skills later. / MA (Child Kinetics), North-West University, Potchefstroom Campus, 2015

The reactivity of group 15 Zintl ions, E₇^3– (E = P, As), towards a number of transition and post-transition metal reagents has been studied. The synthesis and characterisation of the resulting novel cluster anions are described herein. The reactions of E₇^3– with [Cu₅(mes)₅], MPh₂ (M = Zn, Cd) and InPh₃ yielded the Cu–Cu bridged species [Cu₂(E₇)₂]^4– (E = P, As), the group 12 bridged cluster anions [M(E₇)₂]^4– (M = Zn: E = P, As; M= Cd: E = P), and the In-functionalised Zintl ions [E₇InPh<sub>2<sub>]^2–, respectively. P₇^3– and As₇^3– have been found to react with a number of metal salts, namely [M(nbe)₃][SbF₆] and MCl (M = Ag, Au), InCl₃, TlCl and MI₂ (M = Sn, Pb). These reactions formed the Ag–Ag and Au–Au bridged complexes [M₂(HP₇)₂]^2– (M = Ag, Au), the In-bridged species [In(E₇)₂]^3– (E = P, As), the Tl-derivatised Zintl ions [TlE₇]^2– (E = P, As), and the sixteen vertex cluster anions [ME₁₅]^3– (M = Sn, Pb; E = P, As). The reactivity of P₇^3– towards a series of group 8 compounds has also been studied. The reactions of P₇^3– with FeCl₂ and [Ru(PPh₃)₃Cl₂] produced [M(HP₇)₂]^2- (M = Fe, Ru). NMR studies showed that these species can be deprotonated to form [M(P₇)₂]^4– (M = Fe, Ru). These Fe and Ru complexes are isoelectronic with ferrocene. In addition, P₇^3– reacts with [Ru(COD)(η³-CH₂C(CH₃)CH₂)₂] to form [(C₄H₇)P₇Ru(COD)]^2–. Both P₇^3– and As₇^3– undergo transition metal mediated activation reactions in the presence of [Co(PEt₂Ph₂)(mes)₂], yielding [Co(η⁵-P₅){η²-HP₂(mes)}]^2– and [Co([η³-As₃){η⁴-As₄(mes)₂}]^2–, respectively.

The purpose of this project has been to expand the η8 binding mode of the permethylpentalene ligand into uranium, zirconium and hafnium chemistry. All three of these elements have shown intriguing, high-hapticity carbocyclic chemistry and, because of their relatively large size, are excellent candidates for the development of organometallic permethylpentalene chemistry. Chapter one of this thesis will review previous work on η n carbocyclic ring chemistry of these elements, where n = 6 - 8. This introduction will include the unsaturated rings systems where all the ,carbons are bonded to the metal centre, specifically η6 arene systems, η 7 cyclohept.atriene systems, and η 8 cyclooctatetraene and pentalene systems. Species of lower hapticity (e .g. the η 6 binding mode of cycloheptatriene) will not be covered but reviews, where available, will be referenced. Chapter two documents the successful synthesis and characterisation of η 8 permethylpentalene uranium (IV) species. Initially, the uranocene equivalent, UPn*2 was synthesised and characterised structurally, magnetically and electrochemically. From here, a half-sandwich synthon [U Pn*CI4][Li(TMEDA)h was synthesised which was used for further salt metathesis chemistry in order to make a number of mixed sandwich complexes. Chapter three is an account of the synthesis and characterisation of zirconium and hafnium η 8 permethylpentalene species. Initial work focused on the synthesis of a suitable synthon analogous to that used for the previously synthesised titanium species. However, this route was unsuccessful and an alternative species was formed, [MPn*(μ-Cl)3/2]2(μCl)2[Li(THF)x(Et2O)y]. This species could be made on a multi-gram scale and proved to be a sui table synthon for further synthesis. Salt metathesis reactions were undertaken and a number of new species were synthesised and characterised including mixed-sandwich, alkyl, aryl and allyl species. Chapter four reports the results of polymerisation testing that was undertaken for selected synthesised compounds. All compounds catalysed the formation of poly(ethylene), with the group 4 mixed sandwich species being particularly active catalysts. Two of the zirconium species, ZrPn*CpCI and ZrPn*Cp2 were therefore used for further optimisation experiments which were somewhat limited due to the high activity of the compounds. These were useful in gaining insight into conditions that should be investigated on a larger reaction scale. Chapter five gives the full experimental details for all the syntheses described in chapters two and three as well as details of instrumentation used for characterisation, and also gives the respective loadings of catalyst and co-catalyst employed in the polymerisation testing reported in chapter four. Chapter six presents the full characterisation data obtained for the compounds synthesised and the electronic appendix attached as a CD at the back of the thesis contains the crystal data .cif files and the DFT output files (.out). ,

Chapter One introduces molecular irnaging and the modalities available for oncological irnaging. The radioisotopes and imaging agents for Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) are discussed together with the bifunctional chelator approach for radio labelling of biomolecules. Finally, the chemistry and radioisotopes of copper are described, and copper bis(thiosemicarbazonato) complexes introduced in the context of PET irnaging. Chapter Two describes the synthesis and characterisation of novel carboxylate- and maleirnide- functionalised bis(thiosemicarbazonates) and their conjugation to biologically active molecules. Radiolabelling of a chelator-bombesin conjugate demonstrated site-specific labelling at room temperature and preliminary in vitro and in vivo studies confirmed its potential as an imaging agent. Bioconjugation to a model protein and subsequent radiolabelling was also investigated. Chapter Three introduces molecular irnaging of hypoxia with a focus on CuATSM. An overview of the currently accepted mechanism of hypoxia selectivity is presented. The emphasis is placed on the relationship between oxygenation status, uptake and retention which display cell- and tumour- line dependency. Chapter Four presents the synthesis of copper bis(thiosemicarbazonates), radiolabelled either at the metal (64CU) or at the ligand e8F or 123n for mechanistic studies. The physicochemical characteristics of the copper complexes were measured and the complexes evaluated for their in vitro hypoxia selectivity. Chapter Five describes in vitro and in vivo studies of the orthogonally radiolabelled complexes, inclusive of control experiments with [64Cu]CuATS~, the radiolabelled proligand and [64CU]CU2+ salts. In vitro cellular assays, as well as in vivo biodistribution studies including dynamic PET and SPECT were performed. Stability studies contrasting the in vitro and in vivo behaviour were carried out. The collective data suggest that the currently proposed redox trapping mechanism might not provide a full understanding of the factors governing biodistribution and tumour uptake. Chapter Six contains full experimental details for the work described in this thesis.

Framework materials that contain molecular bridging ligands between metal nodes—as seen in coordination polymers—not only give rise to enhanced structural diversity, but also to a range of useful and unusual mechanical properties. This thesis demonstrates the general structure–property relationships that are developed for coordination polymers in order to enable prediction and design of their mechanical properties, and hence structural flexibility. Variable-temperature and -pressure diffraction experiments are employed for the determination of their mechanical properties, namely by calculating thermal expansion and compressibility coefficients. The anomalous and varied mechanical responses observed are rationalised by the important structural features, or the so-called mechanical building units (XBUs), of the coordination polymers. The XBUs are considered within the setting of framework topology, geometry, and composition in order to establish general design principles for targeting different degrees of flexibility within coordination polymers. The XBUs are identified first in silver(I) 2-methylimidazolate, Ag(mim), a framework which is comprised of structural motifs of varying strength, namely argentophilic interactions, hinge points and metal–ligand bonding. The anomalous mechanical responses in Ag(mim) are shown to be rationalised entirely by the XBUs present in the structure. The XBU abstraction is then applied to a range of other coordination polymers and shown to correspond directly with the anomalous responses known in these materials. The metal–ligand–metal linker XBU is investigated further in both cadmium imidazolate, Cd(im)₂, and zinc cyanide, Zn(CN)₂. Here, the linker chemistries are completely different between the two frameworks, but the diamondoid arrangement of the linkers, and thus the topology, is the same. The structural responses of the two frameworks are examined to unravel the extent of topology- and chemistry-driven mechanics. It is found that the topology dominates the atomic displacements of both frameworks, indicating the existence of common soft-mode dynamics which are likely to extend to other coordination polymers with the same topology. The three-dimensional framework-hinging XBUs in zinc isonicotinate, Zn(ISN)₂, and indium deuterium terephthalate, InD(BDC)₂, are considered next. These frameworks have the same topology but contrasting framework geometries, evident from the differing c/a-lattice parameter ratios. In this case, a geometric formalism is derived which can predict the direction of framework mechanical anisotropy in Zn(ISN)₂ and InD(BDC)₂ and other uniaxial coordination polymers. Finally, a family of ABX₃-type transition metal(II) formates are investigated, where both the B-site and A-site cations are varied. The chemical modifications give rise to variations in B- or A-site cation sizes, which are found to correlate with the magnitude of mechanical responses. These structure–mechanical property relationships—based upon framework topology, geometry and composition—are presented in separate chapters, and in each case generalised so that they can be applied to a range of coordination polymers. Hence the design principles determined here can provide the materials science community with an intuition on the type and magnitude of responses possible in these materials under different external stimuli.