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Structural Design and Catalytic Applications of Homogenous and Heterogeneous Organometallic Lewis Acids Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Benjamin Russell Reiner Graduate Program in Chemistry The Ohio State University 2018 Dissertation Committee Casey R. Wade, Advisor Christo S. Sevov Hannah Shafaat 1 Copyrighted by Benjamin Russell Reiner 2018 2 Abstract A broad goal of organometallic chemistry to use ligand and catalyst design to effect useful chemical transformations. Rational design of novel ligands has allowed us to study how binuclear, redox active, or supramolecular frameworks can engender new or enhanced chemical reactivity. One of the major barriers to adopting gold into traditional two electron redox cycling is the high potential required to access gold(III). Use of a binuclear gold framework can eschew this issue by distributing the redox load over multiple metal sites. Phosphorus ylide gold dimers support a wide range of oxidation states which has allowed study into the reductive processes involved in the thermolysis of arylated or alkylated gold(III,III) complexes. Additionally, the binuclear framework allows access to a dicationic gold(II,II) complex that exhibits markedly superior Lewis acid mediated catalytic activity compared to gold complexes supported by other ligands or in other oxidation states. While rylene imides have a variety of applications in electrical energy storage devices, their use as redox non-innocent ligands has been severely underexplored. Rigorous electrochemical and photochemical investigations have shown how reduced naphthalene diimide (NDI) species interact with charge dense redox inactive cations such as Mg2+ or Li+. Moreover, chemical reduction revealed formation of a discrete dimeric complex that features strong coordination of the NDI oxygen atoms to the Mg centers. Electrochemical i and structural studies into the interaction between rylene imides and transition metals was accomplished by using NDI or phthalimide ligands decorated with pyridyl-thiazole units. Cyclic voltammetry of the ensuing Co2+ and Zn2+ complexes uncovered important structure function relationships between the redox state of the ligand and the accessibility of metal- borne reduction events. Metal-organic frameworks (MOFs) are a hybrid class of material which allow translation of well-established principles in homogenous catalysis into a heterogenous context. Diphosphine pincer complexes facilitate a multitude of impressive catalytic processes but can suffer from deactivation processes that limit their long term activity. Immobilization of diphosphine pincer complexes as linkers within MOFs can extend catalytic lifetime by suppressing deleterious side reactions. Lattice immobilized Pd PNNNP N N − (P N P = 2,6-(HNPAr2)2C5H3N; Ar = p-C6H4CO2 ) pincer complexes demonstrate longer catalytic lifetimes in Lewis acid mediated catalysis compared to homogenous analogs. Additionally, immobilized Pd PNNNP pincer complexes were found to exhibit size selective catalytic activity which was not for a homogenous analog. ii Dedication Tho' much is taken, much abides; and tho' We are not now that strength which in old days Moved earth and heaven, that which we are, we are; One equal temper of heroic hearts, Made weak by time and fate, but strong in will To strive, to seek, to find, and not to yield. For Katie iii Acknowledgments Science, like life, is never accomplished alone and to stand on the shoulders of giants and call yourself tall is morally unacceptable. Below are people who are smarter, wittier, stronger, more disciplined, more handsome, and more ethically sound than I could ever hope to be. Here be giants. My research advisor, Prof. Casey Wade is a tremendously good scientist and his mentorship and friendship have driven me to be a markedly better chemist. His unwavering sense of scientific rigor and demands for perfection continue to resonate with me to this day. His patience in training and tolerating bad jokes have not gone unnoticed and never will. My undergraduate advisor, Prof. Jeffery Byers, never treated me any different than a graduate student which was both exciting and more often horrifying. I enjoyed this sort of trial-by-fire training and I owe an absurd amount of my knowledge and success to his early mentorship. Dr. Christine Goldman inspired me to stay in chemistry. Her enthusiasm and passion for teaching is underappreciated and she deserves a thousand thanks and a tripled salary. I’d also like to thank Dr. David Healey, my music instructor through college, for teaching me two things: 1) proper breath control determines quality of sound and 2) saying someone “has potential” should be wildly insulting because if you have potential you should use it. Dr. Sue Pochapsky trained me how to use and think about NMR spectroscopy and I always desperately appreciated any knowledge she would spare during cryogen fills. iv I’d also like to acknowledge Prof. Christine Thomas for, purposely or not, being a wonderful mentor and friend. During my graduate tenure, I have had the opportunity to work with some of the kindest and most intelligent people I’ve ever had the good fortune to meet. Sarah Baranowski has a deliciously simple outlook on life and draws success from the air. Mark Bezpalko was (and still is) easily bribed with banana bread and beer to solve crystal structures quickly and can play a mean game of soccer. Keith Fritzsching and I had more late night science talks than I care to admit but, for better and worse (usually worse), we always went back to lab. Cami Schneider, Jeff Slater, and Andrew Chen were unnecessarily helpful during the early lab set up. This included both helping us find chemicals and the good beer. Katie Gramigna is the smartest and sweetest person I know. Her friendship means the world to me and always will. I’m not sure I ever deserved her. My roommate Jeff Mckee lived with me for seven years through college and most of graduate school. We ran the Boston Marathon twice together. For lack of the proper paperwork and kicking us into a higher tax bracket we could have been common law married. He was and is a great friend. Nate Walka and Connor Rooney are better people and teachers than I will ever fathom and I have always enjoyed our every conversation on teaching, writing, the role of the modern scientist, and why Muppet Treasure Island is the greatest movie ever made. I’d like to thank our past Wade Lab postdocs and current lab members. I enjoyed working with Abebu Kassie and eating her Ethiopian food. I wish I got to do more of both. v Samantha Burgess was a brilliant labmate and Neil Mucha was always kind even when watching BC lose to Clemson live on national television. To my parents: your support has never wavered or faltered. It’s your fault I’m a chemist. To Katie Bien: all these people had to tolerate me some of the time but you had to tolerate me all of the time. For this and all, thank you and I love you. vi Vita May 2013........................................................B.S. Chemistry, Boston College 2013 – 2015....................................................Graduation Teaching Assistant, Brandeis University 2015 – 2017.....................................................NMR Teaching Assistant, Brandeis University 2018 – present..................................................Graduate Research Assistant, Department of Chemistry, The Ohio State University Publications Reiner, B. R.; Mucha, N. T.;Rothstein, A; Temme S. J.; Duan, P.; Schmidt-Rohr, K.; Foxman, B. M.; Wade. C. R. Zirconium Metal-Organic Frameworks Assembled from Pd and Pt PNNNP Pincer Complexes: Synthesis, Postsynthetic Modification, and Lewis Acid Catalysis. Inorg. Chem. 2018. 57, 2663–2672 Reiner, B. R.; Foxman, B. M.; Wade, C.R. Electrochemical and Structural Investigation of the Interactions between Naphthalene Diimides and Metal Cations. Dalton Trans. 2017. 46, 9472 – 9480. Reiner, B. R.; Bezpalko, M. W.;Foxman, B. M.; Wade, C.R. Lewis Acid Catalysis with Cationic Dinuclear Gold(II,II) and Gold(III,III) Phosphorus Ylide Complexes. Organometallics. 2016, 35, 2830 – 2935. (selected as Cover Art) Fields of Study Major Field: Chemistry vii Table of Contents Abstract ............................................................................................................................i Dedication ..................................................................................................................... iii Acknowledgments .......................................................................................................... iv Vita ...............................................................................................................................vii Table of Contents ........................................................................................................ viii List of Tables ................................................................................................................. xi List of Figures ...............................................................................................................xii Chapter 1: Introduction .................................................................................................... 1 1.1 Ligand Design and Catalysis .................................................................................. 1 1.2. The catalytic and stoichiometric activity of binuclear gold ylide complexes
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