Physical Sciences and Mathematics Commons^™

Reactions Of First-Row Transition Metal Complexes In Bis(Alkoxide) Ligand Environments With Diazoalkanes: Formation Of Carbenes Versus Reductive Coupling To Form Bridging Tetrazenes, Amanda Grass

Wayne State University Dissertations

This dissertation focuses on the design and reactions of novel late transition metal carbene complexes featuring alkoxide ligand environments. The high-valent cobalt carbene Co(OR)2(=CPh2) (OR = OCtBu2Ph), featuring short Co=C bond of 1.773(3) Å, was previously reported from the reaction of Co(OR)2(THF)2 with diphenyldiazoalkane. Magnetic and spectroscopic (EPR) studies demonstrated Co(OR)2(=CPh2) to be a low-spin S = ½ complex. Computational studies, in agreement with experimental data, suggested that the electronic structure of Co(OR)2(=CPh2) lies between intermediate spin Co(III) anti-ferromagnetically coupled to a carbene radical and a Co(IV) alkylidene. This dissertation began with investigation of this complex in carbene transfer reactivity. …

Synthesis Of Discrete Transition Metal (Ni, Fe, Co, Mn) Phosphide Nanoparticles: Compositional Effect On Catalytic And Magnetic Properties, Da Li

Wayne State University Dissertations

This dissertation research is focused on the synthesis, characterization of binary and ternary transition metal (Ni, Co, Fe, Mn) phosphide nanomaterials and their catalytic and magnetic properties.

A phase-control strategy enabling the arrested-precipitation synthesis of nanoparticles of Ni5P4 and NiP2 is presented. The composition and purity of the product can be tuned by changing key synthetic levers, including the metal precursor, the oleylamine (OAm) and Trioctylphosphine (TOP) concentrations, temperature, time and the presence or absence of a moderate temperature soak step to facilitate formation of Ni and/or Ni-P amorphous nanoparticle intermediates.

New CoxFe2-xP nanoparticles (0 ≤ x ≤ 2), Co2-xMnxP …

Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media, Derek James Averill

Wayne State University Dissertations

The formation of carbon-carbon bonds is of great interest to synthetic chemists because these bonds make up the majority of biologically active compounds. The Mukaiyama aldol reaction is a Lewis-acid-catalyzed carbon-carbon bond-forming reaction that has the ability to produce optically active β-hydroxy carbonyls which can be found in many pharmaceuticals and natural products. Because of precatalyst instability towards hydrolysis, anhydrous solvents are commonly used. Recent efforts have focused on water-tolerant versions of enantioselective Mukaiyama aldol reactions because of the financial and environmental benefits of using aqueous media. Consequently, the Lewis-acidic and water-tolerant features of Ln³⁺ ions have aroused great …

Development Of Ruthenium/Terpyridine Complexes For Water Oxidation, Dakshika Chandrashani Wanniarachchi

Wayne State University Dissertations

The work presented in the dissertation is focused on developing catalysts for water oxidation. In this regard, a series of unsysmmetrical ruthenium complexes of type [Ru(terpy-R)(phen-X)Cl]PF6 where terpy-R= 4'-(4-methylmercaptophenyl)-2,2':6'2"-terpyridine and phen-X=H (1), X= 5-nitro (2), X=5,6-dimethyl (3), and X= 3,4,7,8-tretramethyl (4) was synthesized as precursors for self-assembled monolayers. Water oxidation properties of these complexes were evaluated in the presence of (NH4)2[Ce(NO3)6] as the sacrificial oxidant by measuring catalytic turnover number (TON) after 24 h of reaction time and rate of dioxygen evolution in solution during early stages of catalysis. The results revealed that all complexes 1 - 4 are catalytic …