Physical Sciences and Mathematics Commons^™

Studies On Molecular Sieve Crystallization And Heteroatomic Substitution, Adam R. Macintosh

Electronic Thesis and Dissertation Repository

Molecular sieves have been scientifically and industrially important materials since their inception. These porous, crystalline networks of tetrahedrally coordinated atoms bridged by oxygen are known for their extremely high surface area and low density, making them excellent systems for catalysis. The framework of the AlPO₄ family of molecular sieves is itself non-catalytic, but through heteroatomic substitution these materials can diversify into the catalytically active silicoaluminophosphate (SAPO) and metalloaluminophosphate (MAPO) families of heterogeneous acid and redox catalysts. Research into the methods by which these substitutions occur, and the effects therein on the crystallization of the sieves, is of great importance, …

Investigations Of Zeolite Growth By Atomic Force Microscopy (Afm), Donghan Chen

Electronic Thesis and Dissertation Repository

Zeolites are microporous materials that have been used extensively in various fields. A better understanding on their crystallization process is important for their investigations. Atomic force microscopy (AFM) is a powerful tool for studying the growing traces on the crystal surface, providing information regarding the relation between surface events and framework structure. This thesis mainly focuses on the surface investigation of several zeolites and microporous materials. ZSM-11 single crystals were synthesized under hydrothermal conditions, and their crystallization process was monitored by AFM, PXRD, SEM, and SSNMR. SAPO-34 prepared under both HTS and DGC conditions showed morphological differences that are related …

Ionothermal Synthesis Of High Silica Zeolites In Deep Eutectic Solvents (Des), Zheng Sonia Lin

Electronic Thesis and Dissertation Repository

Phase-pure high silica zeolites have been synthesized using different deep eutectic solvents for the first time. ZSM-5 was made in tetrapropylammonium bromide/pentaerythritol. The reaction is affected by the amounts of seeding, water content, and organic structure-directing agent (SDA). Sodalite and ZSM-39 were prepared in tetramethylammonium chloride (TMACl)/1, 6-hexanediol by using the mineralizing agents NaOH and NH₄F, respectively. In urea/choline chloride, ZSM-5, Beta, ZSM-39, and ZSM-11 were made by using different organic SDAs in the presence of fluoride. The reaction temperature and the choice of organic SDA affect the type of structures being produced.

The crystallization of ZSM-39 in …

Reactivity Of Dimethylplatinum(Ii) Complexes With Peroxides, Kyle R. Pellarin

Electronic Thesis and Dissertation Repository

This thesis describes a study of dimethylplatinum(II) complexes containing bidentate nitrogen donor ligands. This work deals with the oxidative addition of peroxides and focuses on synthesis, characterization and reaction mechanisms of these complexes.

Dimethylplatinum(II) complexes were reacted with oxidants dimethyldioxirane (DMDO), meta-chloroperbenzoic acid (m-CPBA) and phthaloyl peroxide. The use of these oxidants has allowed for the synthesis of novel platinum(IV) complexes by oxidative addition and the formation of unique supramolecular networks. The formation of both trans- and cis-oxidative addition products was controlled by the type of oxidant utilized. By varying the ligand design of the …

Reactions Of Platinum Complexes With Dimethylamine-Borane, Shawn M. Robinson

Electronic Thesis and Dissertation Repository

This thesis describes a study of the reactions of platinum complexes with dimethylamine-borane (DMAB) as models for alkane activation. It is concluded that sigma-borane complexes of platinum(II) or platinum(IV) will be difficult to synthesize or even to detect as intermediates in hydride transfer from boranes to platinum.

The complex [PtMe(O₂CCF₃)(bpy)] reacts with DMAB to form an intermediate [PtMeH(bpy)] complex, which undergoes reductive elimination of methane with further degradation to give platinum(0) and free 2,2’-bipyridine. The addition of methyl acrylate to the reaction allowed the trapping of the platinum-hydride, producing [PtCl(CHMeCO₂Me)(bpy)] and [Pt(CHMeCO₂Me) …

The Synthesis And Reactivity Of New Pnictogen(Iii) Cations, Allison L. Brazeau

Electronic Thesis and Dissertation Repository

Chelating nitrogen based ligands are well known for their use with transition metals while their chemistry with p-block elements has been relatively underdeveloped. This thesis examines the structure, bonding and reactivity of group 15 elements supported by a pyridyl tethered 1,2-bis(imino)acenaphthene (“clamshell”) and various homo- and heteroleptic guanidinate frameworks.

The unique “clamshell” ligand contains a pendant Lewis base and has been used to support N-heterocyclic phosphenium and arsenium cations. Reactivity studies with the phosphorus analogue demonstrate the ability of the ligand to act as a Lewis base, while the phosphorus centre provides a Lewis acidic site, showing the amphoteric …

Structural Motifs Of Novel Metallothionein Proteins, Duncan E K Sutherland

Electronic Thesis and Dissertation Repository

Metallothioneins (MT) are a family of small cysteine rich proteins, which have been implicated in toxic metal detoxification, protection against oxidative stress, and as a metallochaperone. The most well studied member of the family is the mammalian MT, which consists of two domains: a β-domain with 9 cysteine residues, which sequesters 3 Cd²⁺/Zn²⁺, and an α-domain with 11 cysteine residues, which sequesters 4 Cd²⁺/Zn²⁺. The exact functions of MT are unknown but must relate to its metalation status. Several areas that could lead to the assignment of function include 1) the determination …

Solid-State Nuclear Magnetic Resonance Spectroscopy Of Unreceptive Quadrupolar Nuclei In Inorganic Materials, Andre Sutrisno

Electronic Thesis and Dissertation Repository

Preparation and characterization of inorganic materials is a crucial practice because understanding the relationship between structure and property is important for improving current performance and developing novel materials. Many metal centers in technologically and industrially important materials are unreceptive low-γ quadrupolar nuclei (i.e., possessing low natural abundance, low NMR frequencies and large quadrupole moments) and they usually give rise to very broad NMR resonances and low signal-to-noise ratios, making it difficult to acquire their solid-state NMR spectra. This thesis focuses on the characterization of inorganic materials using solid-state NMR (SSNMR) spectroscopy at very high magnetic field of …

Syntheses, Hydrogen Bonding, And Metal Coordination Studies Of New Ferrocene Peptide Conjugates, Craig D. Colquhoun

Electronic Thesis and Dissertation Repository

The main goal of the research was the synthesis of new ferrocene peptideconjugates, to study the role of hydrogen bonding interactions, and the coordinationproperties of these systems. Ferrocene peptide conjugates have been extensivelystudied as models of protein secondary structures. Of particular interest weredisubstituted ferrocene derivatives such as ferrocene dicarboxylic acid, which have beenshown to be important in the design of peptide mimics. The inter-ring spacing betweentwo cyclopentadienyl rings in ferrocene has shown to be appropriate for forminghydrogen bonds between conjugated peptide chains, which are attached to the twocyclopentadienyl rings. Inter-ring spacing has proven to be of great importance for theformation …