This thesis describes the methods of communication in the Integrated Rescue System, considering especially its basic components. The theoretical part focuses on the description of the Integrated Rescue System components and the regulations determining the competence and connection of the basic IRS components and between each other. The research part evaluates possibilities of the investigated IRS components, their tools for connection and communication, and the principles which are usually used in their work. All knowledge are summarised at the end of the thesis. Included is also a proposal for particular types of activities of the Integrated Rescue System components as regards joint action - the organization of connection. This part determines the basic communication rules which could be helpful in mutual communication of the Integrated Rescue System components dealing with extraordinary events.

Made available in DSpace on 2014-06-11T19:22:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-15Bitstream added on 2014-06-13T19:49:09Z : No. of bitstreams: 1 gama_dt_me_rcla.pdf: 262318 bytes, checksum: 30a2b6db0585880a09c93dc12f159783 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As crianças com Transtorno do Desenvolvimento da Coordenação (TDC) são caracterizadas pelo fraco desempenho motor apresentado, considerando suas idades e inteligência. Existem evidências de que as crianças com TDC apresentam lentidão no movimento, pobre coordenação intra e inter-membros e falta de precisão no movimento. No entanto, não somente a fase de execução do movimento é afetada nas crianças com TDC, mas também a fase de preparação motora. O objetivo do presente estudo é investigar o uso da informação prévia por crianças com TDC e com DT na preparação e execução motora em tarefa de alcance ao alvo. Os participantes do estudo foram 15 crianças com TDC, com idades entre 7 e 8 anos, pareadas em idade e sexo com igual número de crianças com Desenvolvimento Típico (DT). A tarefa consistia no alcance a um de dois alvos desenhados sobre uma mesa digitalizadora (tablete). Os participantes desempenharam a tarefa experimental em três condições: condição correta (i.e. a dica indicava em qual lado apareceria o estímulo), condição incorreta (i.e. a dica indicava o lado contrário ao do aparecimento do estímulo); e condição neutra (i.e. nenhuma informação era disponibilizada). Os resultados indicam que ambos os grupos não são capazes de utilizar a informação prévia correta para reduzir o tempo da preparação motora, pois não houve diferença significativa no tempo de reação entre a condição correta e a neutra e que ambos os grupos são mais lentos para preparar o movimento na condição de fornecimento de informação prévia incorreta em comparação a condição neutra. Em relação à execução motora, as crianças com TDC precisam significativamente de mais tempo para iv fazer os últimos ajustes na trajetória do movimento para o alcance ao alvo e, ainda, a execução do movimento pelas crianças com TDC... / Developmental coordination disorder, especially in children, is characterized by a performance below expected when compared with children of the same age and intelligence. There is evidence that children with DCD display movement slowness, poor interlimb and intralimb coordination, and lack of movement accuracy. However, not only the movement execution is slowness in DCD children but also the motor preparation. The purpose of the present study was to examine whether providing information in an advance to a motor response (i.e., precue) children with DCD would be capable of reducing motor preparation time (i.e., reaction time – TR). Participants were 15 children with DCD aged between 7 and 8 years and the same number of typically developing (TD) children matched by age and gender. The experimental task consisted of discrete aiming movements to one of two targets on a digitizing tablet. Participants performed the experimental task in three different conditions: valid precue (i.e., was the cue in which the advance information was correct); invalid precue (i.e., was the cue in which the advance information was incorrect); and neutral condition (i.e., none advance information was available). The results indicated that DCD and DT children were not able to use valid precue to reduce motor preparation time and that DCD and DT children 65 increase motor preparation time with invalid precue. With respect to motor execution, DCD children spend more time for final adjustments to reach the target than DT children. Also, movement execution of DCD children tended to be less fluent compared with DT children. Overall, the results of the present study do not give support to previous... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:29:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-21Bitstream added on 2014-06-13T20:38:24Z : No. of bitstreams: 1 silva_pb_dr_araiq_parcial.pdf: 270201 bytes, checksum: 585f52f1db0eaf23bbed52ec96e38cc7 (MD5) Bitstreams deleted on 2015-06-25T13:01:12Z: silva_pb_dr_araiq_parcial.pdf,. Added 1 bitstream(s) on 2015-06-25T13:03:28Z : No. of bitstreams: 1 000712513_20160921.pdf: 237556 bytes, checksum: ed160724489b8fe3d24f76bb41a4fa85 (MD5) Bitstreams deleted on 2016-09-23T13:56:38Z: 000712513_20160921.pdf,. Added 1 bitstream(s) on 2016-09-23T13:57:52Z : No. of bitstreams: 1 000712513.pdf: 10287291 bytes, checksum: 9a55b72e349e9fa39a285e594f6348e4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cobre é o terceiro elemento de transição mais abundante no corpo humano e está presente no sítio ativo de enzimas que participam de reações oxidativas como a citocromo oxidase ou a superóxido dismutase. Além disso, é reconhecido há muito tempo que compostos de cobre são capazes de inibir uma gama de fungos e bactérias. Dentro dessa perspectiva, o objetivo principal deste trabalho consistiu na síntese, caracterização e investigação da atividade antibacteriana de complexos de cobre(II) contendo como ligantes moléculas bioativas {etambutol (EMB), isoniazida (INH) e pirazinamida (PZA)}, ácido isonicotínico (Hina), diaminas {N-dodecil-1,2-etanodiamina (L1), N-tetradecil-1,2-etanodiamina (L2), N,N´-bisdodecil-1,2-etanodiamina (L3), N-dodecil-1,3-propanodiamina (L4), N-tetradecil-1,3- propanodiamina (L5)} e aminoálcoois {N-tetradecil-2-amino-etanol (L6), N-tetradecil-2-amino-propanol (L7), 2-(tetradecilamino)-2´-metil-1-propanol (L8) e N-tetradecildietanolamino (L9)}. Foram preparados 14 compostos de cobre(II) inéditos: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) e [CuCl2L9] (20). Os compostos foram caracterizados por análise elementar, espectroscopia vibracional no infravermelho, espectroscopia eletrônica no UV/Visível, ressonância paramagnética eletrônica e por análsie térmica (TGA e DTA). O composto [CuCl2(L4)2] H2O (15) teve sua estrutura determinada por difratometria de raios X de monocristal. A superfície dos compostos foi analisada por microscopia eletrônica de varredura e a textura porosa dos compostos [Cu(NCS)2(INH)2]·5H2O (4) e... / Copper is the third most abundant transition metal element in biological systems and was recognized as essential biological element in 1920. The use of copper salts as fungicide has been known for a long time. The main purpose of this study consisted in the synthesis, spectroscopic characterization and investigation of the antibacterial activity of copper(II) complexes containing biological active molecules {ethambutol (EMB), isoniazid (INH) and pyrazinamide (PZA)}, isonicotinic acid (Hina), diamines {Ndodecyl- 1,2-ethanediamine (L1), N-tetradecyl-1,2-ethanediamine (L2), N,N´-bisdodecyl-1,2- ethanediamine (L3), N-dodecyl-1,3-propanodiamine (L4), N-tetradecyl-1,3-propanodiamine (L5)} and amino alcohols {N-tetradecyl-2-amino-ethanol (L6), N-tetradecyl-2-amino-propanol (L7), 2- tetradecylamino)-2´-methyl-1-propanol (L8) and N-tetradecyldiethanolamine (L9)}. Fourteen new complexes were prepared: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) and [CuCl2L9] (20). The compounds were characterized by elemental analysis, infrared spectroscopy, UV-Vis spectroscopy, electron paramagnetic resonance, thermogravimetry and differential thermal analysis. The compound [CuCl2(L4)2]·H2O (15) had its structure determined by single crystal X ray diffraction. The surface of the compounds was analysed by scanning electron microscopy, and the porous texture of the complexes [Cu(NCS)2(INH)2]·5H2O (4) and [Cu(NCO)2(INH)2]·4H2O (5) was analysed by nitrogen adsorption-desorption (ASAP technique), which showed that both complexes are mesopores. The copper(II) complexes were submitte... (Complete abstract click electronic access below)

Orientador: Regina Celia Galvão Frem Di Nardo / Banca: Marlus Chorilli / Banca: Victor Marcelo Deflon / Banca: Alexandre Cuin / Banca: Gustavo Von Poelhsitz / Resumo: O cobre é o terceiro elemento de transição mais abundante no corpo humano e está presente no sítio ativo de enzimas que participam de reações oxidativas como a citocromo oxidase ou a superóxido dismutase. Além disso, é reconhecido há muito tempo que compostos de cobre são capazes de inibir uma gama de fungos e bactérias. Dentro dessa perspectiva, o objetivo principal deste trabalho consistiu na síntese, caracterização e investigação da atividade antibacteriana de complexos de cobre(II) contendo como ligantes moléculas bioativas {etambutol (EMB), isoniazida (INH) e pirazinamida (PZA)}, ácido isonicotínico (Hina), diaminas {N-dodecil-1,2-etanodiamina (L1), N-tetradecil-1,2-etanodiamina (L2), N,N'-bisdodecil-1,2-etanodiamina (L3), N-dodecil-1,3-propanodiamina (L4), N-tetradecil-1,3- propanodiamina (L5)} e aminoálcoois {N-tetradecil-2-amino-etanol (L6), N-tetradecil-2-amino-propanol (L7), 2-(tetradecilamino)-2'-metil-1-propanol (L8) e N-tetradecildietanolamino (L9)}. Foram preparados 14 compostos de cobre(II) inéditos: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) e [CuCl2L9] (20). Os compostos foram caracterizados por análise elementar, espectroscopia vibracional no infravermelho, espectroscopia eletrônica no UV/Visível, ressonância paramagnética eletrônica e por análsie térmica (TGA e DTA). O composto [CuCl2(L4)2] H2O (15) teve sua estrutura determinada por difratometria de raios X de monocristal. A superfície dos compostos foi analisada por microscopia eletrônica de varredura e a textura porosa dos compostos [Cu(NCS)2(INH)2]·5H2O (4) e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Copper is the third most abundant transition metal element in biological systems and was recognized as essential biological element in 1920. The use of copper salts as fungicide has been known for a long time. The main purpose of this study consisted in the synthesis, spectroscopic characterization and investigation of the antibacterial activity of copper(II) complexes containing biological active molecules {ethambutol (EMB), isoniazid (INH) and pyrazinamide (PZA)}, isonicotinic acid (Hina), diamines {Ndodecyl- 1,2-ethanediamine (L1), N-tetradecyl-1,2-ethanediamine (L2), N,N'-bisdodecyl-1,2- ethanediamine (L3), N-dodecyl-1,3-propanodiamine (L4), N-tetradecyl-1,3-propanodiamine (L5)} and amino alcohols {N-tetradecyl-2-amino-ethanol (L6), N-tetradecyl-2-amino-propanol (L7), 2- tetradecylamino)-2'-methyl-1-propanol (L8) and N-tetradecyldiethanolamine (L9)}. Fourteen new complexes were prepared: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) and [CuCl2L9] (20). The compounds were characterized by elemental analysis, infrared spectroscopy, UV-Vis spectroscopy, electron paramagnetic resonance, thermogravimetry and differential thermal analysis. The compound [CuCl2(L4)2]·H2O (15) had its structure determined by single crystal X ray diffraction. The surface of the compounds was analysed by scanning electron microscopy, and the porous texture of the complexes [Cu(NCS)2(INH)2]·5H2O (4) and [Cu(NCO)2(INH)2]·4H2O (5) was analysed by nitrogen adsorption-desorption (ASAP technique), which showed that both complexes are mesopores. The copper(II) complexes were submitte... (Complete abstract click electronic access below) / Mestre

Ces travaux consistent en l’étude selon trois axes de la chimie de coordination des ligands de type acyle-hydrazone, faisant suite à l’isolation d’un complexe binucléaire de manganèse (III) portant un tel ligand, et montrant un fort couplage ferromagnétique. Le développement de leur chimie de coordination avec des éléments de la première série de transition a permis la synthèse de plusieurs complexes binucléaires, permettant d’étudier la relation entre les structures moléculaires de ces systèmes, et leurs propriétés magnétiques. En parallèle, une série de polymères de coordination de métaux alcalins et alcalino-terreux portant des ligands acyle-hydrazone fonctionnalisés par un groupement sulfonate a été étudiée. Enfin, la synthèse de deux ligands dérivés d’un anthracène est présentée, celle-ci est accompagnée d’une étude de leurs propriétés de coordination. / This work consists in the study of the coordination chemistry of acyl-hydrazone ligands, following the discovery of a manganese (III) dinuclear complex showing a strong ferromagnetic coupling. The development of the acyl-hydrazone coordination to first-row transitional metals resulted in several dinuclear complexes allowing the study of the relationship between their structural and magnetic properties. In a second part the study of several coordination polymers of alkali and alkali-earth metals bearing acyl-hydrazone ligands functionalized with a sulfonate group is presented. Finally the synthesis of two anthracene-based ligands is presented along a study of their coordination properties.

Les réseaux de coordination, ou Metal Organic Frameworks (MOFs), sont des architectures cristallines hybrides organiques-inorganiques qui présentent des propriétés découlant de leurs compostions et de leurs architectures. L'objectif de ce travail fut la synthèse contrôlée de nouveaux réseaux de coordination homo- (MOFs) et hétérométalliques (M'MOFs) à base de ligands dipyrrines (dpms). Dans une première partie, une stratégie de synthèse basée sur l'auto-assemblage a permis l'obtention d'une nouvelle famille de réseaux constituée de MOFs luminescents [CdII(dpm)2] et de MOFs [NiII(dpm)2]. Dans une seconde partie, l'utilisation d'une stratégie séquentielle a permis de préparer des M'MOFs de type grille basés sur différents cations métalliques primaires (CuII, PdII, ZnII) et différents nœuds métalliques secondaires (CdCl2, Cd(NCS)2, Fe(NCS)2). Ces M'MOFs font partie des rares exemples d’architectures modulables conçues par une approche rationnelle et prédictible. De plus, il a été montré que ces composés pouvaient être synthétisés en une seule étape par une méthode avantageuse de synthèse "one pot". Pour finir, une stratégie "zip-Unzip-Rezip" consistant à convertir des MOFs préalablement formés en M'MOFs hétérométalliques par l'emploi de ligands auxiliaires a été mise au point. Cette nouvelle voie permet d'incorporer aisément de la fonctionnalité dans des architectures. / Coordination networks or Metal Organic Frameworks (MOFs) are hybrid organic-Inorganic crystalline architectures displaying properties resulting from their composition and organization. The aim of this work was to synthesize, in a controlled manner, dipyrrin based new homometallic (MOFs) and heterometallic (M'MOF) coordination networks.In the first part, a strategy based on self-Assembly leading to the formation of a new family of luminescent networks [CdII(dpm)2] MOFs and [NiII(dpm)2] MOFs is described.In a second part, generation of grid-Type M'MOFs based on different primary cations (CuII, PdII, ZnII) and secondary metallic nodes (CdCl2, Cd(NCS)2, Fe(NCS)2) by a sequential strategy is presented and discussed. These M'MOFs are among the rare examples of predesigned architectures displaying substantial modularity. Importantly, it has been also demonstrated that these architectures may be efficiently prepared by a "one pot" procedure. Finally, a "zip-Unzip-Rezip" strategy consisting in the conversion of preformed MOFs into M'MOFs using auxillary ligands was developed. This unprecedented approach allows the introduction of functionality within the architectures.

Bimetallic complexes are known to have unique electronic properties and are used in a variety of organic transformations as catalysts. The use of naphthalene-bridged bis- triazoles (NBT) for bimetallic complexes is unknown. NBTs have the unique property of being fluorescent stemming from a twisted intramolecular charge transfer. With the non- coplanar geometry and the distance between the 1,2,3-triazole rings, we hypothesized that 1,8-bis(4-phenyl-2H-1,2,3-triazol-2-yl)naphthalene (12) would be a suitable ligand to synthesize a bimetallic complex. The synthesis of 12 was optimized for large scale synthesis and was synthesized on a 78 mmol scale in 15% total yield. Metal complexation trials were conducted on 12 and several insoluble solids were observed.

This thesis has focused on functionalising heterometallic [nPr2NH2][Cr7NiF8(O2CtBu)16], {Cr7Ni}, clusters, which are candidates for qubits in quantum information processing, by substitution of the peripheral carboxylic acids to produce [nPr2NH2][Cr7NiF8(O2CtBu)16-x(O2CR)], where R is a group with the desired functionality. The use of pyridyl and carboxylic acid containing groups has been investigated for the purposes of linking {Cr7Ni} units, either through metal sites and metallic clusters. The work has resulted in the synthesis of multi-component, polymetallic, nano-scale constructs where in some cases where the individual building blocks have been pre-synthesised and isolated prior to synthesis, with examples of three, four and six {Cr7Ni} units bound to a variety of metal clusters. A selection of aromatic functionalised carboxylic acids has also been successfully substituted onto the ring periphery with the prospect of binding to aromatic surfaces such as graphene and carbon nanotubes. These include fluorenylmethyloxycarbonyl protected amino acids, which opens a potential avenue to grafting of peptide chains to the periphery.

Introduction : Les enfants ayant un trouble de l‘acquisition de la coordination (TAC) éprouvent de la difficulté à apprendre des gestes moteurs, particulièrement ceux demandant de la coordination motrice. Des nombreuses études en neuroimagerie ont mis en évidence une diminution de l‘activité neuronale au niveau du cervelet, ce qui pourrait être à l‘origine des difficultés d‘apprentissage moteur chez les enfants ayant un TAC. Augmenter l‘activité neuronale au niveau du cervelet afin d‘améliorer l‘apprentissage et la coordination motrice pourrait être une avenue prometteuse. La stimulation à courant direct (SCD) anodale permet d‘augmenter l‘activité neuronale de la région stimulée. L‘application de la SCD anodale au niveau du cervelet a montré une amélioration de l‘apprentissage moteur chez des populations en santé ou ayant des troubles neurologiques. À notre connaissance, aucune étude n‘a évalué l‘efficacité de l‘application de la SCD sur l‘apprentissage moteur des enfants ayant un TAC. Objectif : Ce projet vise à évaluer l‘efficacité de la SCD anodale appliquée au niveau du cervelet sur l‘apprentissage moteur et la coordination motrice du membre supérieur des enfants ayant un TAC. Méthodologie : Une étude expérimentale à devis avant-après avec un groupe témoin équivalent a été réalisée. Dix-neuf enfants âgés entre 10 et 17 ans ont été randomisés dans un des deux groupes (stimulation active ou stimulation placebo). Durant trois sessions, les participants ont reçu un courant anodal (de 2mA ou placebo) au niveau du cervelet. La stimulation a été effectuée durant 20 minutes pendant que les enfants réalisaient simultanément une tâche de pianotage sur le clavier d‘un ordinateur. Cette tâche, appelée « Serial Reaction Time Task (SRTT) », permet de mesurer la vitesse de réponse et le taux d‘erreur, lesquels ont été utilisés pour évaluer l‘apprentissage moteur. La coordination motrice du membre supérieur a été évaluée par le test doigt-nez (TDN) avant et après chaque application de la SCD. Résultats : L‘application de la SCD n‘a pas eu effet statistiquement significatif sur l‘apprentissage moteur, bien qu‘une tendance ait été observé quant à la réduction du taux d‘erreur pour le groupe actif par rapport au groupe placebo (p=0.072). Aucune différence statistiquement significative n‘a été observée pour la vitesse de réponse et la coordination motrice entre les 2 groupes. Conclusion : La SCD anodale pourrait potentiellement améliorer l‘apprentissage moteur chez les enfants ayant un TAC, particulièrement en regard de la diminution du taux d‘erreur. Cependant, plus de recherches sont nécessaires afin d‘explorer si la SCD pourrait être un outil ayant un potentiel thérapeutique intéressant pour bonifier l‘efficacité des interventions visant l‘apprentissage moteur des enfants ayant un TAC. / Abstract : Introduction: Children with developmental coordination disorder (DCD) have difficulties learning motor tasks, especially for the ones requiring motor coordination. Numerous neuroimaging studies demonstrated a decrease in neuronal activity in the cerebellum, what might be responsible for motor learning difficulties in children with DCD. Increasing neuronal activity in the cerebellum might be an interesting avenue to improve learning and motor coordination. Anodal transcranial direct current stimulation (a-tDCS) has been shown to increase neuronal activity of the stimulated region, and to improve motor learning in healthy adults or patients with neurological disorders. To our knowledge, no study has assessed the tDCS effectiveness on motor learning for children with DCD. Objective: The present study evaluates the effect of cerebellar a-tDCS application on the motor learning and upper limb coordination of children with DCD. Methods: A pre-post experimental study with an equivalent control group was performed. Nineteen children aged 10-17 years were randomized in one of the two groups (active or placebo stimulation). During three sessions, participants received an anodal stimulation (2mA or placebo) on the cerebellum. The stimulation was carried out for 20 minutes while children simultaneously performed the Serial Reaction Time Task (SRTT), used to document motor learning through response speed and error rate. The motor coordination of the upper limb was evaluated by the finger-nose test (FNT) before and after each tDCS session. Results: The cerebellar a-tDCS could not significantly improve motor learning but a clinical reduction on error rate for the active group versus placebo group (p=0.072). The tDCS application did not show significantly improvement on speed and motor coordination between two groups. Conclusion: The a-tDCS could potentially improve motor learning by decreasing the error rate of children with DCD. However, more researches are needed to explore if the tDCS could be an interesting therapeutic tool to improve the effectiveness of motor learning interventions for children with DCD.

The ability of a deprotonated aza-crown ether to allow isolation of soluble lanthanide and yttrium complexes has been investigated. A convenient route to these complexes has been demonstrated by the protonolysis reactions of Ln[(N(SiMe₃)₂]₃ with 4,13-diaza-18-crown-6. NMR spectroscopy and X-ray crystallography revealed a C₂V structure consisting of a basket shaped geometry. The successful protonolysis route has been extended to the preparation of stable alkyls, dialkyls, and alkyl cations of yttrium and zirconium stabilized by deprotonated aza- crown macrocycles. A yttrium, alkyl complex containing deprotonated diaza-18-crown-6 has been prepared by the protonolysis route. The thermal stability and reactivity of this complex were investigated. This alkyl reacts with terminal alkynes to produce a complex equilibrium between the colourless monomeric and dimeric alkynides and a purple Z-butatrienediyl (ie.RC=C=C=CR²⁻) coupling product. NMR studies demonstrate that electron poor alkynes favour coupling and that the carbon-carbon double bond forming process is readily reversible at room temperature. The flexibility of the deprotonated diaza-crown ligand is apparent from the isolation of both cis and trans-zirconium dibenzyl complexes from the protonolysis of tetrabenzyl zirconium with 4,13-diaza-18-crown-6. The structure of both isomers were investigated by NMR spectroscopy and X-ray crystallography. Both the cis and trans-isomers cleanly converted to the stable cation either by protonolysis with [n-Bu₃NH]⁺[BPh₄]⁻ or by alkyl abstraction with B(C₆F₅)₃. The reactivity of the alkyl cation derived from the reaction with B(C₆F₅)₃ was investigated. The reaction of this cation with t-BuNC gave a vinylamide complex following a 1,2-proton rearrangement of an initially formed iminoacyl. Two members of the still rare yttrium dialkyl class of compounds were isolated using monoanionic, deprotonated aza-crown ethers as supporting ligation. The dialkyl complexes were synthesized by protonolysis of Y(CH₂SiMe₃)₃(THF)₂ with either aza-18-crown-6 or aza-15-crown-5. NMR and X-ray analyses of the yttrium dialkyl supported by aza-18-crown-6 indicates a trans-dialkyl geometry while NMR analysis of the aza-15-crown-5 analog indicates a cis-dialkyl geometry. Reaction of the trans-dialkyl complex with CO afforded a trans-dienolate complex formed by the migration of SiMe₃. Alkyl abstraction from the trans-dialkyl complex using B(C₆F₅)₃ allowed generation of the first yttrium, alkyl cation. / Graduate