Discharge of many organic contaminants (OCs) to the environment from industries such as pharmaceuticals, pesticides, dyestuffs, and chemical intermediates is one of the major concerns to human health and the ecosystem due to their high toxicity. Existing water and wastewater treatment techniques were not specifically designed to remove OCs, and the elimination rate can vary from negligible to over 90%. Therefore, development of treatment technologies to efficiently remove OCs from water and wastewater effluents is required. Polymeric resins are an alternative for treatment since they can selectively target certain OCs as they can be custom-synthesized during polymerization by including desired functional groups to the matrix. However, additional efforts and cost are needed for the regeneration of the exhausted resins and recycling of the sorbed contaminants. Palladium based catalysts supported on polymeric resins are a promising method to overcome regeneration problems and convert contaminants to less toxic chemicals. The main goals of this research were to (1) develop predictive models for the sorption of cationic OCs by resins based on a mechanistic understanding of the sorption mechanisms of a range of cationic OCs on two cation exchange resins and (2) synthesize novel resin-based Pd catalysts to selectively remove two toxic contaminants, i.e., 4-chlorophenol and 4-nitrophenol, convert them to less toxic chemicals, and evaluate the possibility of in situ regeneration of the spent resins. The sorption study indicated that electrostatic (ion exchange) and nonelectrostatic (adsorption) interactions between nonpolar moieties of solute and sorbent have synergistic effects on sorption. It also established predictive models for estimating the sorbed concentrations of a target contaminant on a given resin at any environmentally relevant pH. Our findings point to the significant role of adsorption in the overall catalytic reactivity. The rate determining step (RDS) switched from adsorption to surface reaction with increasing concentration of the reactant. This observation was confirmed by good fitting of the reaction kinetics to the Langmuir-Hinshelwood model developed based on the respective RDS. Our results demonstrated that Pd-resin composites are advantageous to water treatment because they can avoid the conventional resin regeneration process and enable recycling of reaction products of smaller environmental impacts. / Civil Engineering

In recent years two-phase catalysis has been established as a new field of catalyzed processes and has achieved industrial-scale importance in olefin hydroformylation. Two-phase reactions have a number of advantages, for example, ease of separation of catalyst and product, catalysts can be tailored to the particular problem, use of special properties and effects of water as a solvent, and low environmental impact. For higher olefins (* C6), the reaction suffers low activity due to low water solubility of higher olefins. Tricesium analog of TPPTS, m,m,m-trisulfonated triphenylphosphine, was synthesized and fully characterized. Two-phase olefin hydroformylation with Rh(acac)(CO)2 was investigated. The results indicated that both activity and selectivity (linear to branch aldehyde ratio) are similar to Rh/TPPTS system. The salt effect showed that increase the solution ionic strength will increase the selectivity and decrease the activity in the olefin hydroformylation with TPPTS. A new surface active phosphine, trisulfonated tris-m-(3henylpropyl)phenylphosphine, was synthesized and fully characterized. The results of biphasic olefin hydroformylation were consistent with aggregation of the ligand. The two phase 1-octene hydroformylation results showed that with only 3 methylene groups, there is no difference between the para and meta position of C3 group. A new chelating diphosphine, tetrasulfonated 2,2'-bis{di[p-(3 phenylpropyl)phenyl]phosphinomethyl}-1,1'-biphenyl,was prepared and fully characterized. Its application in two-phase hydroformylation of olefin showed enhanced activity and selectivity compared to the non-chelated phosphine analog. Finally, homogeneous asymmetric hydrogenation was carried out in the presence of a chiral surfactant in an attempt to affect asymmetric induction. The catalytic results showed that at a surfactant/Rh ratio of 25, the asymmetric hydrogenation of AACA-Me (a-Acetamidocinnamic Acid Methyl Ester) in methanol has no effect on asymmetric induction with the introduction of this chiral surfactant. / Master of Science

Endohedral metallofullerenes (EMFs) have attracted increasing attention during past decades due to their novel structures and potential applications in a variety of fields such as biomedical applications and molecular electronics. This dissertation addresses the structural characterization and hydrogenation of EMFs. A family of novel large cage yttrium-based TNT EMFs Y₃N@C₂ₙ (n=40-44) was prepared, separated, and structurally characterized for the first time. The structure of Y₃N@C₂ₙ (n=40-44) is proposed by the experimental and computational ¹³C NMR studies. The first ⁸⁹Y NMR results for Y₃N@<I>Iₕ</i>-C₈₀, Y₃N@<I>Cₛ</i>-C₈₄ and Y₃N@<I>D₃</i>-C₈₆ reveal a progression from isotropic to restricted (Y₃N)⁶⁺</sup> cluster motional processes. The di-metallic EMF Y₂C₉₄ is distinguished as a metal-carbide based EMF, Y₂C₂@<I>D₃</i>-C₉₂. The carbide within the cage is successfully detected by ¹³C NMR. The scalar J_Y-C coupling between the yttrium atoms and the C₂ unit within the C₉₂ cage is successfully observed, suggesting the C₂ unit rotates rapidly around the yttrium atoms. Two paramagnetic endohedral metalloheterofullerenes, Y₂@C₇₉N and Gd₂@C₇₉N, were also synthesized and characterized. The EPR study demonstrated that the spin density is mainly localized between the two metallic ions. A spin-site exchange system could be constructed between Y₂@C₇₉N and the organic donor TMPD. Being a unique paramagnetic material, Gd₂@C₇₉N displays an unusual stability over a wide temperature range, which could be very useful in optical and magnetic areas. Functionalization of EMFs is another point of interest in this dissertation. Hydrogenated Sc₃N@C₈₀ was synthesized and characterized. Our study demonstrated that the Sc₃N@C₈₀ can be fully hydrogenated and the pristine Sc₃N@C₈₀ can be recovered from Sc₃N@C₈₀H₈₀ after being heated in vacuum. The hydrogenated EMFs could be potential hydrogen storage materials. / Ph. D.

The work described in this thesis is focused on the development of new bidentate iridium complexes and their applications in the asymmetric reduction of olefins, ketones and imines. Three new types of iridium complexes were synthesized, which included pyridine derived chiral N,P-iridium complexes, achiral NHC complexes and chiral NHC-phosphine complexes. A study of their catalytic applications demonstrated a high efficiency of the N,P-iridium complexes for asymmetric hydrogenation of olefins, with good enantioselectivity. The carbene complexes were found to be very efficient hydrogen transfer mediators capable of abstracting hydrogen from alcohols and subsequently transfer it to other unsaturated bonds. This hydrogen transferring property of the carbene complexes was used in the development of C–C and C–N bond formation reactions via the hydrogen borrowing process. The complexes displayed high catalytic reactivity using 0.5–1.0 mol% of the catalyst and mild reaction conditions. Finally chiral carbene complexes were found to be activated by hydrogen gas. Their corresponding iridium hydride species were able to reduce ketones and imines with high efficiency and enantioselectivity without any additives, base or acid. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 5: Submitted. Paper 6: Manuscript.</p><p> </p>

<p>The synthesis of 2-aza-norborane derivatives is presented. The use of these compounds in preparation of Ir catalysts for asymmetric hydrogenations is described. The evaluation and optimization of the catalysts as well as the mechanistic aspects of the catalytic process are discussed.</p><p>The use of non-activated iminodieniphiles in stereoselective aza-Diels-Alder reaction has expanded the scope of the reaction and provided a convenient root for preparation of 2-aza-norboranes, analogues of which were developed into novel bicyclic 2-aza-norbornyl-oxazoline ligands for Ir-catalyzed asymmetric transfer hydrogenations. Using ths Ir complexes acetophenone was hydrogenated in 79% ee.</p><p>2-Aza-norbornyl-oxazolines were also developed into novel N,P-ligands. Resulting phosphine-oxazolines were evaluated in Ir-catalyzed asymmetric hydrogenation of structurally diverse imines and olefins.</p><p>Optimization of ligands was performed through: 1) Alteration of the stereoconfiguration at the 5’-position as well as variation of the size and geometry of the substituents at this position; 2) Screening through various phosphine substituents of the ligand. Both directions of optimization reflect on the influence of the ligands’ sterik bulk on stereoselectivity of catalytic process. High performance catalysts were developed for both transformations allowing asymmetric hydrogenation of imines with 92% ee and asymmetric hydrogenation of olefins with 99% ee.</p><p>Possible mechanisms for these transformations were suggested based on computational studies. Selectivity model for rationalization of results of Ir-catalyzed olefin hydrogenation also was designed.</p>

The synthesis of 2-aza-norborane derivatives is presented. The use of these compounds in preparation of Ir catalysts for asymmetric hydrogenations is described. The evaluation and optimization of the catalysts as well as the mechanistic aspects of the catalytic process are discussed. The use of non-activated iminodieniphiles in stereoselective aza-Diels-Alder reaction has expanded the scope of the reaction and provided a convenient root for preparation of 2-aza-norboranes, analogues of which were developed into novel bicyclic 2-aza-norbornyl-oxazoline ligands for Ir-catalyzed asymmetric transfer hydrogenations. Using ths Ir complexes acetophenone was hydrogenated in 79% ee. 2-Aza-norbornyl-oxazolines were also developed into novel N,P-ligands. Resulting phosphine-oxazolines were evaluated in Ir-catalyzed asymmetric hydrogenation of structurally diverse imines and olefins. Optimization of ligands was performed through: 1) Alteration of the stereoconfiguration at the 5’-position as well as variation of the size and geometry of the substituents at this position; 2) Screening through various phosphine substituents of the ligand. Both directions of optimization reflect on the influence of the ligands’ sterik bulk on stereoselectivity of catalytic process. High performance catalysts were developed for both transformations allowing asymmetric hydrogenation of imines with 92% ee and asymmetric hydrogenation of olefins with 99% ee. Possible mechanisms for these transformations were suggested based on computational studies. Selectivity model for rationalization of results of Ir-catalyzed olefin hydrogenation also was designed.

In Michael J. Krische research group we are developing new transition metal catalyzed Carbon-Carbon (C-C) forming reactions focusing on atom economy and byproduct free, environmental friendly approaches. We have developed a broad family of C-C bond forming hydrogenations with relative and absolute stereocontrol which provide an alternative to stoichiometric organometallic reagents in certain carbonyl and imine additions. Inspiring from the group work my goal was to develop new reactions, extend the scope of our group chemistry and their application towards synthesis of biologically active natural products. I have been part of enantioselective Rh catalyzed Aldol reaction of vinyl ketones to different aldehydes. Also, we have found that iridium catalyzed transfer hydrogenation of allylic acetates in the presence of aldehydes or alcohols results in highly enantioselective carbonyl allylation under the conditions of transfer hydrogenative. Based on this reactivity a concise enantio- and diastereoselective synthesis of 1,3-polyols was achieved via iterative chain elongation and bidirectional iterative asymmetric allylation was performed, which enables the rapid assembly of 1,3-polyol substructures with exceptional levels of stereocontrol. The utility of this approach stems from the ability to avoid the use of chirally modified allylmetal reagents, which require multistep preparation, and the ability to perform chain elongation directly from the alcohol oxidation level. This approach was utilized for the total synthesis of (+)-Roxaticin from 1,3-propanediol in 20 longest linear steps and a total number of 29 manipulations. Further, advancements were made in iridium catalyzed C-C bond formation under transfer hydrogenation. While methallyl acetate does not serve as an efficient allyl donor, the use of more reactive leaving group in methallyl chloride compensate for the shorter lifetime of the more highly substituted olefin π-complex. Based on this insight into the requirements of the catalytic process, highly enantioselective Grignard-Nozaki-Hiyama methallylation is achieved from the alcohol or aldehyde oxidation levels. Also, a catalytic method for enantioselective vinylogous Reformatsky- type aldol addition was developed in which asymmetric carbonyl addition occurs with equal facility from the alcohol or aldehyde oxidation level. Good to excellent levels of regioselectivity and uniformly high levels of enantioselectivity were observed across a range of alcohols and aldehydes. / text

This thesis is divided into three main results chapters that reflect the path my research took. In the first results chapter, the first organocatalyst for the carbonyl-ene reaction was discovered and found to give high conversion using 1,3-bis(3,5-bis(trifluoromethyl)phenyl)thiourea. Various carbonyl and alkene precursors were examined in the ene reaction in both catalysed and uncatalysed reactions. It was found that ene reactions using fluoral and ethyl trifluoropyruvate give higher rates of reaction when compared to other carbonyl compounds. A novel enantiopure thiourea was synthesised and the ene reaction was catalysed enantioselectively to 33% e.e. In an attempt to catalyse the reaction to a further extent a new thiourea bonded to a P(=S)R2 group was developed. However, the intramolecular hydrogen bonding of this catalyst was thought to be so strong that this it did not catalyse the reaction. The synthesis of a chiral phosphoric acid was achieved but this was an unsuccessful catalyst in the ene reaction. Two component achiral thiourea and chiral acids were also examined in the ene and Mannich-type reaction. The new easily synthesised thiourea for this reaction has an interesting intermolecular hydrogen bonding coordination in the solid state. Asymmetric fluorination of ketoesters using palladium is a dynamic kinetic resolution. In the 2nd chapter cationic palladium complexes were synthesised and used to determine the optimum parameters for bidentate ligands in this reaction. Four carbon chain phosphines were found to give the highest conversion for this reaction among those ligands tested such as 1,4-bisdiphenylphosphinobutane (bite angle 99º). A new bis-phosphinous amide chiral ligand was developed with a bite angle of 96.7º. The dichloropalladium complex of this phosphine was isolated and structurally characterised. The use of the palladium complex in asymmetric fluorination was attempted however this was found to be unsuccessful. Mechanistic studies reveal that the formation of the desired cationic catalyst did not occur under conditions shown to work well for other palladium phosphine complexes. The ligand was investigated further in hydrogenation reactions. The phosphinous amide was protected as its borane and was used in the rhodium catalysed hydrogenation of alkenes to give high conversion and up to 93% e.e. The borane protected phosphinous amide was also found to catalyse the hydrogenation of acetophenone using copper complexes with up to 84% e.e for the hydrogenation of acetophenone, although conversion was quite low.

Durant les darreres dècades, el disseny de processos en el marc de la química sostenible ha anat creixent de forma exponencial. La recerca constant de processos mes benignes amb el medi ambient ha implicat un gran esforç per obtenir millors rendiments mitjançant l'activació de llocs específics, i possant especial èmfasi amb el control de la quimio-, la regio- i la enantioselectivitat, punts crucials per a l'economia atómica. En aquest sentit, els dissolvents juguen un paper crític, i com podrà veure's al llarg d'aquesta memòria..Aquesta Tesi s'enfoca en l'ús de mitjans de reacció alternatius i sostenibles, com són els líquids iònics (ILs), el diòxid de carboni supercrític (scCO2) i la barreja de ambdós dissolvents, amb l'objectiu de disminuir l'ús de dissolvents orgànics convencionals i la seva aplicació en els següents processos catalítics: hidrogenació asimètrica, reacció de Suzuki d'acoblament creuat C-C, reacció d'alquilació al·lílica asimètrica i la hidrogenació de arens. / In the last decades, the design of processes in the framework of the sustainable chemistry has been exponentially growing. The constant searching of cleaner processes has led to a lot of effort to obtain higher yields by activation of specific sites, and improving chemo-, regio- and enantio-selectivities, which are crucial from a point of view of an atom economy strategy. In this sense, solvents play a critical role. This PhD thesis focuses on the use of alternative sustainable reaction media such as ionic liquids (ILs), supercritical carbon dioxide (scCO2) and mixtures of both solvents in different catalytic processes, with the aim of decreasing the use of conventional organic solvents applied in the following catalytic reactions: homogeneous and supported rhodium catalysed asymmetric hydrogenation, biphasic palladium catalysed Suzuki C-C cross-coupling, homogeneous palladium catalysed asymmetric allylic alkylation, and ruthenium and rhodium nanoparticles catalysed arene hydrogenation were tested.

Fischer-Tropsch synthesis (FTS), developed in the early 1900's, is defined as the catalytic conversion of H2 and CO to hydrocarbons and oxygenates with the production of H2O and CO2. Accurate microkinetic modeling can in principle provide insights into catalyst design and the role of promoters. This work focused on gaining an understanding of the chemistry of the kinetically relevant steps in FTS on Fe catalyst and developing a microkinetic model that describes FTS reaction kinetics. Stable Al2O3-supported/promoted (20% Fe, 1% K, 1% Pt) and unsupported Fe (99% Fe, 1% Al2O3) catalysts were prepared and characterized. Transient experiments including temperature programmed desorption (TPD), temperature programmed hydrogenation (TPH), and isothermal hydrogenation (ITH) provided insights into the chemistry and energetics of the early elementary reactions in FTS on Fe catalyst. Microkinetic models of CO TPD, ITH, and FTS were developed for Fe catalyst by combining transition state theory and UBI-QEP formalism. These models support the conclusion that hydrocarbon formation occurs on Fe via a dual mechanism involving surface carbide and formyl intermediates; nevertheless, hydrocarbon formation is more favorable via the carbide mechanism. Carbon hydrogenation was found to be the rate determining step in the carbide mechanism. CO heat of adsorption on polycrystalline Fe at zero coverage was estimated to be -91.6 kJ/mol and -64.8 kJ/mol from ITH and FTS models respectively, while a mean value of -50.0 kJ/mol was estimated from the TPD model. Statistically designed steady-state kinetic experiments at conditions similar to industrial operating conditions were used to obtain rate data. The rate data were used to develop a microkinetic model of FTS. FTS and ITH appear to follow similar reaction pathways, although the energetics are slightly different. In both cases, hydrocarbon formation via the carbide mechanism was more favorable than via a formyl intermediate while carbon hydrogenation was the rate determining step. Promotion of Fe with K does not alter Fischer-Tropsch synthesis reaction pathways but it does alter the energetics for the steps leading to the formation of CO2. This phenomenon accounts for the CO2 selectivity of 0.3 observed for K-promoted Fe against 0.17 observed for un-promoted Fe. A Langmuir Hinshelwood rate expression derived from the microkinetic model was put into a fixed bed FTS reactor design code; calculated reactor sizes, throughput, temperature profiles and conversion are similar to those of pilot and demonstration FTS reactors with similar feed rates and compositions.