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Book Multidentate Phosphino alkene Ligands and Their Late Transition Metal Complexes

Download or read book Multidentate Phosphino alkene Ligands and Their Late Transition Metal Complexes written by Amanda G. Jarvis and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The synthesis and characterisation of a new class of multidentate conformationally flexible phosphino-alkene ligands, called dbaPHOS (127) and monodbaPHOS (128), are described is this PhD thesis. The related phosphine sulphide ligands, namely dbaTHIOPHOS (137) and monodbaTHIOPHOS (149), have also been prepared. The coordination chemistry of the novel ligands was investigated with a variety of late-transition metals, including Cu, Rh, Pd and Pt. X-ray crystal structure determination of the complexes containing these ligands highlights the multiple coordination modes and versatility of each ligand system. The ability of the 1,4-dien-3-one backbone to adopt different conformational geometries around metal centers is of particular note. DbaPHOS (127) was found to act as a cis- and trans-chelating bisphosphine in both square planar PdII and PtII complexes. The 1,4-dien-3-one motif is hemilabile; exchange between coordinated and non-coordinated alkenes is observed in both the Pd0 complex, 167, and the related cationic CuI complex, 193. An investigation into the CuI complexes' activity in the cyclopropanation of styrene, as catalysts, showed that they are commensurate with other recently reported systems. In addition to the coordination chemistry of the novel ligand systems, some interesting findings emerged in the ligand synthesis and characterisation studies. For example, monodbaTHIOPHOS (149) undergoes an interesting solid-state [2+2] intramolecular cycloaddition transformation, giving cycloadduct, 206. Furthermore, 2-hydroperoxytetrahydrofuran was found to be an impurity in the microwave-assisted Horner-Wadsworth-Emmons reaction of 2-(diphenylthiophosphine)benzaldehyde (136) with 1,3-bis-(ethoxyphosphonato)-acetone (130) to give of dbaTHIOPHOS (137) and an unexpected THF insertion product, 138. The latter is explained by a side reaction involving the reduced compound, tetrahydrofuran-2-ol, derived from 2-hydroperoxytetrahydrofuran.

Book Multidentate Phosphine alkene Ligands and Their Late transition Metal Complexes

Download or read book Multidentate Phosphine alkene Ligands and Their Late transition Metal Complexes written by and published by . This book was released on 2011 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Phosphorus III Ligands in Homogeneous Catalysis

Download or read book Phosphorus III Ligands in Homogeneous Catalysis written by Paul C. J. Kamer and published by John Wiley & Sons. This book was released on 2012-05-09 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last 60 years the increasing knowledge of transition metal chemistry has resulted in an enormous advance of homogeneous catalysis as an essential tool in both academic and industrial fields. Remarkably, phosphorus(III) donor ligands have played an important role in several of the acknowledged catalytic reactions. The positive effects of phosphine ligands in transition metal homogeneous catalysis have contributed largely to the evolution of the field into an indispensable tool in organic synthesis and the industrial production of chemicals. This book aims to address the design and synthesis of a comprehensive compilation of P(III) ligands for homogeneous catalysis. It not only focuses on the well-known traditional ligands that have been explored by catalysis researchers, but also includes promising ligand types that have traditionally been ignored mainly because of their challenging synthesis. Topics covered include ligand effects in homogeneous catalysis and rational catalyst design, P-stereogenic ligands, calixarenes, supramolecular approaches, solid phase synthesis, biological approaches, and solubility and separation. Ligand families covered in this book include phosphine, diphosphine, phosphite, diphosphite, phosphoramidite, phosphonite, phosphinite, phosphole, phosphinine, phosphinidenene, phosphaalkenes, phosphaalkynes, P-chiral ligands, and cage ligands. Each ligand class is accompanied by detailed and reliable synthetic procedures. Often the rate limiting step in the application of ligands in catalysis is the synthesis of the ligands themselves, which can often be very challenging and time consuming. This book will provide helpful advice as to the accessibility of ligands as well as their synthesis, thereby allowing researchers to make a more informed choice. Phosphorus(III) Ligands in Homogeneous Catalysis: Design and Synthesis is an essential overview of this important class of catalysts for academic and industrial researchers working in catalyst development, organometallic and synthetic chemistry.

Book Diallyphosphines and Phosphine stabilized Germylenes as Versatile Ligands for Transition Metal Complexes

Download or read book Diallyphosphines and Phosphine stabilized Germylenes as Versatile Ligands for Transition Metal Complexes written by Juan Manuel Garcia Garfido and published by . This book was released on 2011 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ligand hybrid design is becoming an increasingly important area of the synthetic activity in organometallic chemistry. The coordination chemistry of diallylphosphines and phosphine-stabilized germylenes has been studied in this thesis. In particular, phosphine-stabilized germylenes have not only been studied by its potential use as ligands for transition metals, but also as possible synthetic tools in organic chemistry. Diallylphosphine behave as bidentate ligands to stabilize cationic rhodium species of type [Rh(COD){?3(P,C,C)RP(CH2CH=CH2)2}][BF4] [R= iPr2N, tBu and Ph]. Hemilabile properties of diallylphosphine ligands have been demonstrated by ligand exchange reactions. In solution, a dynamic equilibrium of exchange between the two allylic double bonds was detected by low temperature NMR analysis. In the same way, the reversible displacement of coordinated allylic double bond by acetonitrile could be observed. Theoretical calculations have been performed to explain the experimental results for the order of reactivity on removing the acetonitrile under vacuum. Germylenes stabilized by coordination of a phosphine ligand have been synthesized and fully characterized. Reactivity studies showed that phosphine-stabilized germylenes are unreactive toward unsaturated compounds, such as: alkyne, alkene and carbonyl derivatives, but reactive toward 2,3-dimethylbutadiene. The reactivity of phosphine-stabilized germylenes toward transition metal complexes have been studied by reaction with the dimer complex [Rh2(μ-Cl2)(COD)2], demonstrating that phosphine-stabilized germylenes are useful ligands with high potential in organometallic chemistry. The first isolable germanium analogue of alkynes, known as germyne, stabilized by coordination of a phosphine ligand has been synthesized and fully characterized. Synthesized germynes rearrange at RT affording a phosphaalkene and a new stable N-heterocyclic germylene. Keywords: Hybrid ligands, hemilabile properties, coordination chemistry, diallylphosphines, phosphine-stabilized germylene, germyne.

Book Chiral Phosphorous Based Ligands in Earth Abundant Transition Metal Catalysis

Download or read book Chiral Phosphorous Based Ligands in Earth Abundant Transition Metal Catalysis written by Junliang Zhang and published by Elsevier. This book was released on 2023-05-27 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chiral Phosphorous Based Ligands in Earth-Abundant Transition Metal Catalysis summarizes the most significant progress in the field of chiral phosphine ligand chemistry and a broad range of earth-abundant transition metal/chiral phosphine ligand-catalyzed enantioselective transformations. The book provides an authoritative and in-depth understanding of important topics about asymmetric catalysis based on earth-abundant transition metals/chiral phosphine ligands, making it ideal for organic chemistry researchers working in the field of asymmetric catalysis, synthetic methodologies and total synthesis.The development of new chiral phosphine ligands to achieve precise stereo control in many earth-abundant transition metal-catalyzed reactions is a very important field in organic synthesis, materials science and medicinal chemistry. The asymmetric synthesis promoted by transition metal/chiral phosphine ligands provides one of the most ideal ways to produce valuable optically active chemicals. Includes a discussion of state-of-the-art asymmetric organic reactions mediated by earth-abundant transition metals and chiral phosphine ligands Features the progress and the prospect of chiral phosphine ligands in asymmetric transition metal catalysis Covers the asymmetric reactivity modes of earth-abundant transition metals and phosphine ligands

Book Synthesis and Coordination Chemistry of Multidentate Phosphine Ligands

Download or read book Synthesis and Coordination Chemistry of Multidentate Phosphine Ligands written by Mark Peter Driver and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Transition Metal Complexes of Neutral eta1 Carbon Ligands

Download or read book Transition Metal Complexes of Neutral eta1 Carbon Ligands written by Remi Chauvin and published by Springer. This book was released on 2009-12-18 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents: Yves Canac and Remi Chauvin: Neutral eta1-carbon ligands: beyond carbon monoxide; Esteban P. Urriolabeitia: Ylide Ligands; Wolfgang Petz and Gernot Frenking: Carbodiphosphoranes and related ligands; Mareike C. Jahnke and F. Ekkehardt Hahn: Chemistry of N-Heterocyclic Carbene Ligands; Tsuyoshi Kato, Eddy Maerten, Antoine Baceiredo: Non-NHCs stable singlet carbene ligands; Victorio Cadierno, Sergio E. García-Garrido: All-Carbon-Substituted Allenylidene and Related Cumulenylidene Ligands; Victorio Cadierno, Sergio E. García-Garrido: Heteroatom-Conjugated Allenylidene and Related Cumulenylidene Ligands.

Book Transition Metal Complexes with P N Ligands and Silylenes Synthesis and Catalytic Studies

Download or read book Transition Metal Complexes with P N Ligands and Silylenes Synthesis and Catalytic Studies written by Eva Neumann and published by Cuvillier Verlag. This book was released on 2006-02-15 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term ligand [latin, ligare = bind] has its origin in coordination chemistry. It denotes a molecule that is able to bind to a metal center in most cases via one or several free electron pairs.[1] Ligands can be described by the number of electron-pair donor atoms as monodentate, bidentate, tridentate etc. ligands. The latter are also called chelating ligands [greek, chele = (crab’s) claw]. A typical classification of ligands is according to their electronic properties. They serve either as a σ-donating, σ-donating/π-accepting, or σ,π-donating/π-accepting ligands.[2] A more practical, often encountered approach is the classification of ligands according to their donor atoms, especially when larger molecules and molecules containing heteroatoms are regarded (compare 1.2). Coordination chemistry was already established in the 19th century. In 1893 Alfred Werner suggested an octahedral arrangement of ligands coordinated to a central metal ion for many compounds. This explained, for example, the appearance and reactivity of four different cobalt(III) complexes (Figure 1.1), when CoCl2 is dissolved in aqueous ammonia and then oxidized by air to the +3 oxidation state. The formulas of these complexes can be written as depicted in Figure 1.1. Werner’s work was rewarded with the Nobel prize in 1913.[3]

Book Phosphine Arsine and Stibine Complexes of the Transition Elements

Download or read book Phosphine Arsine and Stibine Complexes of the Transition Elements written by Charles Andrew McAuliffe and published by Elsevier Science & Technology. This book was released on 1979 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Coordination Chemistry of Multidentate Ligands Based on Nitrogen containing Heterocyclic Phenanthridine Moieties

Download or read book Synthesis and Coordination Chemistry of Multidentate Ligands Based on Nitrogen containing Heterocyclic Phenanthridine Moieties written by Rajarshi Mondal and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project explored the synthesis of bi-functional neutral donor ligands using pi-extended phenanthridine system which can stabilize the late transition metals. My interest would be the phenanthridine ring of 14 pi-electron polycyclic heteroaromatic system, which is the building block of my ligands and the properties of this extended aromatic system while binding with late transition metals and comparing with smaller congener quinoline precursor for understanding the effect of site dependent pi extension. The application and properties of designed metal complexes have been extensively studied. The study of using pi-extended phenanthridine as a ligand and its metal complexes would open a new window of opportunities. A synthetic route to bromo functionalization of benzo-fused N-heterocyclic phenanthridine, enabling the constructions of both phosphinophenanthridine and NHC carbene-phenanthridine have been devised, which are heterobifunctional Lewis base containing both phosphine/carbene and phenanthridine donors. The coordination chemistry for both phosphine/carbene ligands with ions of late first-row transition metals has been explored. 4-Bromophenanthridine was synthesized by Suzuki cross-coupling/condensation, 6-substitution was conducted by reaction between phenanthridinone and phosphine(V) oxyhalide. The installation of phosphine was directed by lithium-halogen exchange of 4-bromophenanthridine. The carbenes were placed by the reaction between 6-halophenanthridine and corresponding imidazole in high temperature. A series of halide bridge Cu complexes were synthesized using phosphino-phenanthridine ligand to check the effect of site selective pi-extension on emission property by comparing with smaller congener quinoline based Cu complexes. Further study leads to design of sterically encumbered phenanthridine for diminishing the excited state geometric orientation. A relative effect of counterion in solid-state emission lifetime has also been studied. A group of octahedral d8 metal complexes were synthesized by using both phosphine/carbene ligands to study the metal to ligand charge transfer and its lifetime. The potential of these complexes for use in the field of photosensitizer was also discussed. Phosphino ligand based Fe complexes have been synthesized and their use in the filed of hydrogenation catalysis has also been discussed.

Book The Coordination Chemistry of Positively Charged Phosphine Ligands with Heavy Transition Metal Cations

Download or read book The Coordination Chemistry of Positively Charged Phosphine Ligands with Heavy Transition Metal Cations written by Stephen Wilfred Sheargold and published by . This book was released on 1982 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Hybrid Tertiary Phosphine secondary Amide and Amine Ligands

Download or read book Hybrid Tertiary Phosphine secondary Amide and Amine Ligands written by David Hedden and published by . This book was released on 1985 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Hybrid P E Ligands

Download or read book Hybrid P E Ligands written by Kathryn Mary Allan and published by . This book was released on 2014 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: