Molecular transition metal catalysts offer unique potential for the production of fine chemicals. Chemical processes carried out in the presence of well defined molecular catalysts often only require mild, easily accessible conditions, fewer sacrificial reagents, and can selectively produce a desired product with minimal waste. The active site of a transition metal catalyst can be varied by the use of a hybrid ligand, which employs a combination of groups with different binding affinities for the metal center. Hybrid ligands possessing both substitutionally inert and labile donors, called “hemilabile” ligands, offer an added dimension to catalysis since the weakly binding donor can be displaced from the metal center by a substrate to facilitate the chemical transformation. However this labile donor, in conjunction with an inert donor, can also offer chelate stabilization of the catalyst in the event of coordinative unsaturation at the metal center, a feature which can serve to enhance catalyst longevity. A major goal of the research reported herein is to understand the mechanisms by which hemilabile processes occur within ortho-phosphinoaniline complexes of rhodium and ruthenium and, in turn, how such features might affect catalytic characteristics. To this end, a comparison of catalytic activities of related hemi- and non-labile complexes has been carried out. The ability for two metal atoms held in close proximity to have a cooperative effect on substrate activation or catalysis has also inspired the generation of a series of binuclear compounds bridged by bis(ortho-phosphinoaniline) ligands. In addition to hemilabile and catalytic features, many unique ligand geometries and coordination modes are also observed, particularly by altering the substituents on labile amine donors. Non-labile complexes can also be prepared by deprotonation of labile amine donors to produce ortho-phosphinoanilido species, which display reactivity patterns and structural features distinct from the those of their hemilabile congeners. The amido complexes, which are effective toward ketone transfer hydrogenation and olefin silylation reactions, display interesting features, and in the first case, the possibility of a reaction mechanism unprecedented for transition metal catalysts is discussed. Evidence supporting the operation of such an unexpected mechanism could have important implications for the design and operation of new and more effective transition metal catalysts. / Chemistry

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This thesis describes the catalysed addition of X-H bonds (X = S, O and N) to alkynes using a range of novel rhodium(I) and iridium(I) complexes containing hybrid bidentate phosphine-pyrazolyl, phosphine-imidazolyl and phosphine-N heterocyclic carbene (NHC) donor ligands. The synthesis of novel bidentate phosphine-pyrazolyl, phosphine-imidazolyl (P-N) and phosphine-NHC (PC) donor ligands and their cationic and neutral rhodium(I) and iridium(I) complexes [M(P N)(COD)]BPh4, [M(PC)(COD)]BPh4, [Ir(P-N)(CO)2]BPh4 and [M(P-N)(CO)Cl] were successfully performed. An unusual five coordinate iridium complex with phosphine-NHC ligands [Ir(PC)(COD)(CO)]BPh4 was also obtained. Seventeen single crystal X-ray structures of these new complexes were determined. A range of these novel rhodium and iridium complexes were effective as catalysts for the addition of thiophenol to a variety of alkynes. Iridium complexes were more effective than rhodium analogues. Cationic complexes were more effective than neutral complexes. Complexes with hybrid phosphine-nitrogen donor were more effective than complexes containing bidentate nitrogen donor ligands. An atom-economical, efficient method for the synthesis of cyclic acetals and bicyclic O,O-acetals was successfully developed based on the catalysed hydroalkoxylation. Readily prepared terminal and non-terminal alkyne diols were cyclised into bicyclic O,O-acetals in quantitative conversions in most cases. The efficiency of a range of rhodium and iridium complexes containing bidentate P-N and PC donor ligands as catalysts for the cyclisation of 4-pentyn-1-amine to 2-methyl-1-pyrroline varied significantly. The cationic iridium complexes with the bidentate phosphine-pyrazolyl ligands, [Ir(R2PyP)(COD)]BPh4 (2.39-2.42) were extremely efficient as catalysts for this transformation. Increasing the size of the substituent on or adjacent to the donor led to improvement in catalytic activity of the corresponding metal complexes. The mechanism of the catalysed hydroalkoxylation was proposed to proceed by the initial activation of the alkyne via ?? coordination to the metal centre. The ?? binding of both aliphatic and aromatic alkynes to [Ir(PyP)(CO)2]BPh4 (2.44) was observed by low temperature NMR and no reaction between 2.44 and alcohols was observed. In contrast, the facility in which thiol and amine oxidatively added to 2.44 led the proposal that in the hydrothiolation and hydroamination reaction, the catalytic cycle commences with the activation of the X-H bond (X = S, N) by an oxidative addition process.

This thesis describes the catalysed addition of X-H bonds (X = S, O and N) to alkynes using a range of novel rhodium(I) and iridium(I) complexes containing hybrid bidentate phosphine-pyrazolyl, phosphine-imidazolyl and phosphine-N heterocyclic carbene (NHC) donor ligands. The synthesis of novel bidentate phosphine-pyrazolyl, phosphine-imidazolyl (P-N) and phosphine-NHC (PC) donor ligands and their cationic and neutral rhodium(I) and iridium(I) complexes [M(P N)(COD)]BPh4, [M(PC)(COD)]BPh4, [Ir(P-N)(CO)2]BPh4 and [M(P-N)(CO)Cl] were successfully performed. An unusual five coordinate iridium complex with phosphine-NHC ligands [Ir(PC)(COD)(CO)]BPh4 was also obtained. Seventeen single crystal X-ray structures of these new complexes were determined. A range of these novel rhodium and iridium complexes were effective as catalysts for the addition of thiophenol to a variety of alkynes. Iridium complexes were more effective than rhodium analogues. Cationic complexes were more effective than neutral complexes. Complexes with hybrid phosphine-nitrogen donor were more effective than complexes containing bidentate nitrogen donor ligands. An atom-economical, efficient method for the synthesis of cyclic acetals and bicyclic O,O-acetals was successfully developed based on the catalysed hydroalkoxylation. Readily prepared terminal and non-terminal alkyne diols were cyclised into bicyclic O,O-acetals in quantitative conversions in most cases. The efficiency of a range of rhodium and iridium complexes containing bidentate P-N and PC donor ligands as catalysts for the cyclisation of 4-pentyn-1-amine to 2-methyl-1-pyrroline varied significantly. The cationic iridium complexes with the bidentate phosphine-pyrazolyl ligands, [Ir(R2PyP)(COD)]BPh4 (2.39-2.42) were extremely efficient as catalysts for this transformation. Increasing the size of the substituent on or adjacent to the donor led to improvement in catalytic activity of the corresponding metal complexes. The mechanism of the catalysed hydroalkoxylation was proposed to proceed by the initial activation of the alkyne via ?? coordination to the metal centre. The ?? binding of both aliphatic and aromatic alkynes to [Ir(PyP)(CO)2]BPh4 (2.44) was observed by low temperature NMR and no reaction between 2.44 and alcohols was observed. In contrast, the facility in which thiol and amine oxidatively added to 2.44 led the proposal that in the hydrothiolation and hydroamination reaction, the catalytic cycle commences with the activation of the X-H bond (X = S, N) by an oxidative addition process.

La thématique de recherche développée au cours de cette thèse concerne l’élaboration de nouveaux ligands mixtes ferrocéniques hybrides-(P,N) à conformation contrôlée, robustes et stables à l’air. Ces ligands tétradentes hybrides comportent deux types de fonctions coordinnantes aux propriétés stériques et électroniques distinctes. Leur chimie de coordination avec des métaux tels que l’or ou le palladium a été étudiée et certains complexes d’Au(I) isolés ont été utilisés en catalyse de couplage d’arylation des iodures d’aryles. La première partie de cette thèse porte sur une étude bibliographique concise reflétant la diversité des ligands ferrocénique azotés et hybride-(P,N) et leurs voies de synthèse, pour finalement retracer leur chimie de coordination aux métaux de transition (Pd, Au) ainsi que leurs applications catalytiques. La deuxième partie traite la synthèse d’une famille de composés bis(aminométhyl)-ferrocène et les dérivés associés de manière sélective par amination réductrice du 1,1'- diformylferrocène ou du 1,1'-bis(tert-butyl)-3,3'-diformylferrocène avec une variété d’amines primaires et secondaires. Dans la troisième partie nous présentons les stratégies de synthèse qui ont été utilisées pour la préparation de hybrides-(P,N) ferrocéniques ainsi que leur contrôle conformationnel, et la caractérisation structurale de ces molécules. Leur coordination à des sels de palladium a été étudiée. Les complexes de coordinations correspondants ont étés isolés avec de très bons rendements, et caractérisés en solution par RMN 1H , 13C, 31P, 15N, et à l’état solide par diffraction des rayons X. La quatrième et dernière partie est dédiée à l’étude de la coordination à l’or. Trois nouveaux complexes d’Au(I) dinucléaires, incorporant des ligands ferrocéniques hybride-(P,N), ont étés isolés est caractérisés. L‘un parmi ces complexes a montré une efficacité particulière pour la réaction d’arylation des iodures d’aryles. / The research theme developed during this thesis concerns the development of new hybrid ferrocene hybrid (P, N) ligands with controlled conformation, robust and stable to air. These hybrid tetradent ligands comprise two types of coordinating functions with distinct steric and electronic properties. Their coordination chemistry with metals such as gold or palladium has been studied and some isolated Au (I) complexes have been used in the arylation coupling catalysis of aryl iodides.

Ce mémoire porte sur l’accès simple et peu coûteux à de nouveaux ligands ferrocéniques aminés et aminophosphinés et leur coordination avec des métaux de transition pour des applications en catalyse homogène.Des métallo-ligands aminés flexibles ont été obtenus et caractérisés après amination réductrice du 1,1’-diformylferrocène. D’autres ligands (N,N) rigides ont été isolés au départ du précurseur du 1,1’-di-tert-butyl-3,3’-diformylferrocène. Des aza-ferrocénophanes ont également été facilement préparés avec ces deux précurseurs carbonylés. Lors de la coordination de ces ligands avec le palladium, un palladacycle original a été isolé et caractérisé par diffraction de rayons X.Des ligands ferrocéniques (N,P) ont été obtenus par trois méthodes: i) ortholithiation de ligands ferrocéniques aminés suivie d’un ajout de chlorophosphine, ii) amination réductrice des ferrocènes formylés substitués ou non en présence d’amine portant une fonction phosphine, iii) substitution directe du ferrocène dilithié par des chlorophosphines comportant un hétérocycle azoté. Leur coordination avec du palladium et du platine a été étudiée. Ces métallo-ligands hybrides ont été impliqués dans des réactions de chlorures d’aryle avec des acides arylboroniques (couplage de Suzuki), ainsi que dans la réaction de Sonogashira avec le couplage de bromures et de chlorures d’aryle avec le phénylacétylène / This thesis focuses on simple and inexpensive access to new amino and aminophosphine ferrocenyl ligands and their coordination with transition metals for applications in homogeneous catalysis.Flexible amine metallo-ligands were obtained and characterized after reductive amination of 1,1'-diformylferrocene. Other rigid (N,N) ligands were isolated starting from the precursor 1,1'-di-tert-butyl-3, 3'-diformylferrocene. Aza-ferrocenophanes were also easily prepared with these two formyl precursors. During the coordination of these ligands with palladium, a stable and original palladacycle was isolated and characterized by DRX.(N,P) ferrocenyl ligands were obtained by three methods: i) ortholithiation of aminoferrocenyl ligands followed by addition of chlorophosphines, ii) reductive amination of substituted or not formylferrocene in the presence of amine bearing a phosphine function, iii) direct substitution of dilithiated ferrocene by chlorophosphines with a nitrogen-containing heterocycle. Their coordination with palladium and platinum has been studied. These hybrid metallo-ligands have been implicated in the reactions of aryl chlorides to arylboronic acids (Suzuki cross-coupling), as well as in the Sonogashira reaction involving of coupling aryl bromides and chlorides to phenylacetylene