Download or read book Mechanistic Studies and Design of Supported Transition Metal Complexes written by Terry Zhi Hao Gani and published by . This book was released on 2020 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supported transition metal (TM) complexes are an emerging class of materials with many potential applications in the chemical industry ranging from separations to catalysis. They offer increased tunability and often also improved performance over their bulk heterogeneous counterparts. Their study and rational design is, however, accompanied by several unique considerations and challenges that we address in this thesis. The first part of the thesis broadly develops and applies computational screening strategies for supported TM complexes. First, we detail how weak C-H[superscript ...]O hydrogen bonds can be exploited to increase selectivity of ferrocenium (Fc+)-based polymer electrode materials for formate adsorption over perchlorate adsorption while maintaining reasonable desorption rates in the reduced (ferrocene, Fc) state. Through a systematic characterization of formate and perchlorate interactions with a small (ca. 40) but diverse set of functionalized Fc+ complexes, we identify and rationalize design rules for functionalizations that simultaneously increase selectivity for formate in aqueous environments while permitting rapid release from Fc. Next, we screen a larger (ca. 500) set of model Fe(II) complexes for methane hydroxylation in order to assess if linear free energy relationships (LFERs), extensively developed to reduce the computational cost of computationally screening bulk heterogeneous catalysts, can also be applied to supported single-site TM catalysts. We demonstrate that structural distortions achievable in porous frameworks and chelating ligands break these LFERs by altering relative d-orbital splittings, thereby revealing a potential strategy for improving the activity of these catalysts. Finally, to address a particularly pervasive issue in density functional theory (DFT) studies of first-row open-shell TM complexes, we investigate how the fraction of exact exchange parameterized in the functional affects computed reaction and spin-splitting energies. We rationalize this sensitivity in terms of differences in metal-ligand electron delocalization and introduce the metal-ligand bond valence as a simple, yet robust, descriptor that unifies understanding of exchange sensitivity for catalytic properties and spin-state ordering in TM complexes.
Download or read book Mechanistic Studies on Transition Metal Catalyzed C H Activation Reactions Using Combined Mass Spectrometry and Theoretical Methods written by Gui-Juan Cheng and published by Springer. This book was released on 2017-06-07 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents detailed mechanistic studies on a series of important C-H activation reactions using combined computational methods and mass spectrometry experiments. It also provides guidance on the design and improvement of catalysts and ligands. The reactions investigated include: (i) a nitrile-containing template-assisted meta-selective C-H activation, (ii) Pd/mono-N-protected amino acid (MPAA) catalyzed meta-selective C-H activation, (iii) Pd/MPAA catalyzed asymmetric C-H activation reactions, and (iv) Cu-catalyzed sp3 C-H cross-dehydrogenative-coupling reaction. The book reports on a novel dimeric Pd-M (M = Pd or Ag) model for reaction (i), which successfully explains the meta-selectivity observed experimentally. For reaction (ii), with a combined DFT/MS method, the author successfully reveals the roles of MPAA ligands and a new C-H activation mechanism, which accounts for the improved reactivity and high meta-selectivity and opens new avenues for ligand design. She subsequently applies ion-mobility mass spectrometry to capture and separate the [Pd(MPAA)(substrate)] complex at different stages for the first time, providing support for the internal-base model for reaction (iii). Employing DFT studies, she then establishes a chirality relay model that can be widely applied to MPAA-assisted asymmetric C-H activation reactions. Lastly, for reaction (iv) the author conducts detailed computational studies on several plausible pathways for Cu/O2 and Cu/TBHP systems and finds a reliable method for calculating the single electron transfer (SET) process on the basis of benchmark studies.
Download or read book Mechanistic Studies on Transition Metal catalyzed C H Activation Reactions Using Combined Mass Spectrometry and Theoretical Methods written by Gui-Juan Cheng and published by . This book was released on 2017 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents detailed mechanistic studies on a series of important C-H activation reactions using combined computational methods and mass spectrometry experiments. It also provides guidance on the design and improvement of catalysts and ligands. The reactions investigated include: (i) a nitrile-containing template-assisted meta-selective C-H activation, (ii) Pd/mono-N-protected amino acid (MPAA) catalyzed meta-selective C-H activation, (iii) Pd/MPAA catalyzed asymmetric C-H activation reactions, and (iv) Cu-catalyzed sp3 C-H cross-dehydrogenative-coupling reaction. The book reports on a novel dimeric Pd-M (M = Pd or Ag) model for reaction (i), which successfully explains the meta-selectivity observed experimentally. For reaction (ii), with a combined DFT/MS method, the author successfully reveals the roles of MPAA ligands and a new C-H activation mechanism, which accounts for the improved reactivity and high meta-selectivity and opens new avenues for ligand design. She subsequently applies ion-mobility mass spectrometry to capture and separate the [Pd(MPAA)(substrate)] complex at different stages for the first time, providing support for the internal-base model for reaction (iii). Employing DFT studies, she then establishes a chirality relay model that can be widely applied to MPAA-assisted asymmetric C-H activation reactions. Lastly, for reaction (iv) the author conducts detailed computational studies on several plausible pathways for Cu/O2 and Cu/TBHP systems and finds a reliable method for calculating the single electron transfer (SET) process on the basis of benchmark studies.
Download or read book Kinetic and Mechanistic Studies on Some Transition Metal Complexes written by Mohammed Delwar Hussain and published by . This book was released on 1968 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthetic and Mechanistic Studies of Transition Metal Complexes written by John Arthur Broomhead and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetic and Mechanistic Studies an the Interaction of Transition Metal Complexes with NO and Related Water Exchange Reactions written by Thorsten Schneppensieper and published by . This book was released on 2001 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthetic and Mechanistic Studies on the Cross Coupling Reactions Catalyzed by Ruthenium Complexes written by Ruili Gao and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition metal catalyzed C-H bond activation reaction is a powerful synthetic method for forming functionalized products directly from unreactive hydrocarbons, and has enormous synthetic potentials for developing chemical processes ranging from petroleum products to pharmaceutical agents. In an attempt to mimic the high stereo selectivity and region selectivity of catalytic reactions by transition metal catalysts, recent research has focused on design and synthesis of transition metal complex and the application on the coupling reactions involving C-H bond activation. Herein, we wish to report the highly effective coupling reactions involving C-H bond activation by using well-defined ruthenium catalysts. Ruthenium hydride complex was to found to have high activity and selectivity for hydrosilylation, silyl enol ethers formation and enol esters formation reactions. Throughout the course of the mechanistic investigation of the reactions, we found compelling evidence for mechanism of reactions by spectroscopic, structural techniques and computational (DFT) analysis.
Download or read book Mechanistic Studies of Some Reactions of Square Planar Transition Metal Complexes in Solution written by John Reginald Lyons and published by . This book was released on 1968 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Reactions and Mechanistic Studies of Constrained Transition Metal Pi complexes written by Gary Stephen Silverman and published by . This book was released on 1984 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural and Mechanistic Studies of Some Transition metal Complexes Containing Various Phosphorus and Carbon Donor Ligands written by Jonathan Michael Rosalky and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic Studies for Catalytic Transformation of Small Oxygenates on Transition Metals written by Suyash Singh and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past century, heterogeneous catalysis has played a central role in the development of efficient chemical processes for the conversion of fossil resources to fuels and chemicals, and identification of new, sustainable routes to upgrade renewable carbon sources that minimize the ecological footprint. More recently, unprecedented advances in electronic structure theory and related computational methods have provided a major thrust to the efforts that utilize density function theory (DFT) calculations for developing fundamental atomic-level understanding of these processes, and subsequently designing new and improved catalysts. In this dissertation, a combined theoretical and experimental approach is presented to study the reaction mechanisms for the catalytic conversion of formic acid (FA) and propylene oxide on transition metals. An iterative methodology comprising of DFT calculations, reaction kinetics measurements, and mean-field microkinetic modeling is employed to determine the nature of active sites on supported catalysts, explain the experimentally observed trends, and obtain predictions for the surface environment under reaction conditions. A detailed analysis of the DFT derived thermochemistry and kinetics parameters over a wide range of transition metal surfaces is performed to identify the key reactivity descriptors for FA decomposition on transition metal catalysts, and develop semi-empirical linear correlations that are then used to develop a microkinetic modeling based framework for the identification and design of improved (active and selective) bimetallic alloy catalysts. Finally, the possible utilization and applications of these methods and ideas in other key chemical transformations are proposed, and suggestions for future work are included.
Download or read book Mechanistic Studies in Transition Metal Organic Chemistry written by D. Mead and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthetic Structural and Mechanistic Studies in Early Transition Metal and Actinide Chemistry written by Janet E. Nelson and published by . This book was released on 1991 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics and mechanism studies of the reactions of some transition metal complexes written by Otto Alphonse Gansow and published by . This book was released on 1967 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding Organometallic Reaction Mechanisms and Catalysis written by Valentin P. Ananikov and published by John Wiley & Sons. This book was released on 2014-08-29 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploring and highlighting the new horizons in the studies of reaction mechanisms that open joint application of experimental studies and theoretical calculations is the goal of this book. The latest insights and developments in the mechanistic studies of organometallic reactions and catalytic processes are presented and reviewed. The book adopts a unique approach, exemplifying how to use experiments, spectroscopy measurements, and computational methods to reveal reaction pathways and molecular structures of catalysts, rather than concentrating solely on one discipline. The result is a deeper understanding of the underlying reaction mechanism and correlation between molecular structure and reactivity. The contributions represent a wealth of first-hand information from renowned experts working in these disciplines, covering such topics as activation of small molecules, C-C and C-Heteroatom bonds formation, cross-coupling reactions, carbon dioxide converison, homogeneous and heterogeneous transition metal catalysis and metal-graphene systems. With the knowledge gained, the reader will be able to improve existing reaction protocols and rationally design more efficient catalysts or selective reactions. An indispensable source of information for synthetic, analytical, and theoretical chemists in academia and industry.
Download or read book Configurational Equilibria written by Mary Jane Incorvia Mattina and published by . This book was released on 1970 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On Being Well coordinated A Half century Of Research On Transition Metal Complexes written by John L Burmeister and published by World Scientific. This book was released on 2003-10-14 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: This invaluable book distils the research accomplishments of Professor Fred Basolo during the five decades when he served as a world leader in the modern renaissance of inorganic chemistry. Its primary focus is on the very important area of chemistry known as coordination chemistry.Most of the elements in the periodic table are metals, and most of the chemistry of metals involves coordination chemistry. This is the case in the currently significant areas of research, including organometallic homogenous catalysis, biological reactions of metalloproteins, and even the solid state extended structures of new materials. In these systems, the metals are of primary importance because they are the sites of ligand substitution or redox reactions. In the solid materials, the coordination number of the metal and its stereochemistry are of major importance.Some fifty years of research on transition metal complexes carried out in the laboratory of Professor Basolo at Northwestern University is recorded here as selected scientific publications. The book is divided into three different major research areas, each dealing with some aspect of coordination chemistry. In each case, introductory remarks are presented which indicate what prompted the research projects and what the major accomplishments were. Although the research was of the academic, curiosity-driven type, some aspects have proven to be useful to others involved in projects that were much more applied in nature.
