[PDF] D10 Palladium And Platinum Complexes With Alkene And Diimine Ligands eBook

Author : Allan J. Canty
Publisher : Springer
Page : 195 pages
File Size : 31,23 MB
Release : 2011-02-25
Category : Science
ISBN : 3642174299

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Kyle A. Grice, Margaret L. Scheuermann and Karen I. Goldberg: Five-Coordinate Platinum(IV) Complexes.- Jay A. Labinger and John E. Bercaw: The Role of Higher Oxidation State Species in Platinum-Mediated C-H Bond Activation and Functionalization.- Joy M. Racowski and Melanie S. Sanford: Carbon-Heteroatom Bond-Forming Reductive Elimination from Palladium(IV) Complexes.- Helena C. Malinakova: Palladium(IV) Complexes as Intermediates in Catalytic and Stoichiometric Cascade Sequences Providing Complex Carbocycles and Heterocycles.- Allan J. Canty and Manab Sharma: h1-Alkynyl Chemistry for the Higher Oxidation States of Palladium and Platinum.- David C. Powers and Tobias Ritter: Palladium(III) in Synthesis and Catalysis.- Marc-Etienne Moret: Organometallic Platinum(II) and Palladium(II) Complexes as Donor Ligands for Lewis-Acidic d10 and s2 Centers.

Author : Margaret Louise Scheuermann
Publisher :
Page : 119 pages
File Size : 37,36 MB
Release : 2013
Category : Gold compounds
ISBN :

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Understanding the reactivity of metal complexes with molecular oxygen will facilitate the development of catalysts that can enable the widespread use of molecular oxygen as an oxidant for organic synthesis. This thesis presents two new classes of reactions between metal complexes and molecular oxygen. Neutral five-coordinate Pt complexes were tested for reactivity in the presence of molecular oxygen. In arene solution, the complexes (t̳B̳u̳̳M̳e̳2̳ nacnac)PtMe3 (1, t̳̳B̳u̳M̳e̳2̳ nacnac- = [((4-tBu-2,6-Me2C6H2)NC(CH3))2CH]-), (M̳e̳3̳ Me-nacnac)PtMe3 (2, M̳e̳3̳ Me-nacnac- = [((2,4,6-Me3C6H2)NC(CH3))2CCH3]-), and (t̳B̳u̳2̳ PyPyr)PtMe3 (3, t̳B̳u̳2̳ PyPyr- = 3,5-di-tert-butyl-2-(2-pyridyl)pyrrolide) reacted immediately with oxygen to form peroxo species in which two oxygen atoms bridge between the metal center and a carbon atom in the ligand backbone. In contrast, no reaction between ( i̳P̳r̳2̳ AnIm)PtMe3 (4a, i̳P̳r̳2̳ AnIm− = [o- C66H4-{N(C6H3 i Pr2)}(CH=NC6H3 i Pr2)]−) or (M̳e̳3̳ AnIm)PtMe3 (4b, M̳e̳̳3̳ AnIm− = [o-C6H4- {N(C6H2Me3)}(CH=NC6H2Me3)]−) and oxygen was observed. As activation of oxygen by five- coordinate PtIV species was found to involve cooperation between the metal center and the ligand, the ability of the ligand to participate in the oxygen binding appears to be a vital component. Oxygen atom transfer reactions of the novel peroxo species are also presented. In a separate study, an unusual reaction involving the activation of both molecular oxygen and a C-H bond at the same metal center was investigated. Pd(P(Ar)(tBu)2)2 (15, Ar = naphthyl) was found to react with molecular oxygen at room temperature in arene solvent to form a hydroxide dimer in which one equivalent of phosphine per Pd was lost and the remaining phosphine was cyclometalated through the naphthyl ring. At low temperature, two intermediates were observed. The nature of these intermediates suggests a mechanism involving initial reaction of Pd(P(Ar) (tBu)2)2 with O2 followed by the C-H activation step. In a final chapter unrelated to oxygen reactivity, the generation and characterization of a gold III̳-alkene complex by NMR and X-ray crystallography is presented. Such species have been proposed as intermediates in catalytic reactions but until recently none had been observed.

Author : Peter Maitlis
Publisher : Elsevier
Page : 336 pages
File Size : 47,40 MB
Release : 2012-12-02
Category : Science
ISBN : 0323155324

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The Organic Chemistry of Palladium, Volume 1: Metal Complexes deals with the number of organic reactions that can be catalyzed by palladium, particularly as regards the structures bonding, and reactions of the metal complexes. The book discusses monodentate ligands which are either neutral (carbonyls, isonitriles, carbenes) or anionic (methyl, phenyl, ethynyl, hydride). The text also examines the complexes formed by 1,3-. 1,4-, and 1,5-diolefins where four carbon atoms are bound to the metal. Palladium (II) can undergo a reaction with the 1,3-dienes and results in a ?-allylic complexes where only three carbon atoms are coordinated to the metal. (The bonding situation in complexes 1,4- and 1,5-dienes, where no great interaction between the olefins are similar to that in monoolefin complexes, is straightforward), Olefins can also react with palladium chloride in protic solvents to produce ketones (or aldehydes) or organic coupling products. Some experiments conducted by Huttel et al shows that some palladium was precipitated from the reactions giving lower yields, resulting in various aldehydes and ketones as by products. The book also discusses cyclopentadienyl and benzene complexes. The text can prove beneficial for researchers, investigators and scientists whose works involve organic chemistry, analytical chemistry, physical chemistry and inorganic chemistry.

Author : William P. Griffith
Publisher : Springer Science & Business Media
Page : 371 pages
File Size : 10,29 MB
Release : 2013-06-29
Category : Science
ISBN : 3662091887

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With platinum and rhodium, palladium is one of the most important members of the platinum metal group. The last Gmelin treatment of it was in 1942, and knowledge of its properties and chemistry has made enormous strides since then. This volume is primarily concerned with binary compounds and with the coordination complexes derived from them. Although it is a member of the nickel-palladium-platinum triad, it more closely resernblas platinum in its binary and coordination chemistry, though being a second-row transition element it displays less tendency than does platinum to assume higher oxidation states. ln heterogeneous and homogeneous catalysis, referred to at appropriate points, palladium and its complexes are of great importance in bulk and fine chemieals production, effecting a wide variety of organic transformations. The arrangement of material in this volume follows the traditional Gmelin arrangement. Within each category of compounds or complexes the material is arranged, as usual, in order of ascending metal oxidation states (e. g., palladium(ll) precedes palladium(IV)). The chemistry of the palladium-hydrogen system is so large that it merits a separate volume, so this book starts with the binary oxides and oxopalladates followed by hydroxides, hydroxo complexes and aquo complexes. Then nitrides and nitrates are treated. They are followed by the large chapters on halides and their complexes (172 pages). The largest single chapter in this volume (11 0 pages) deals with chlorides, chloropalladates and other chloro complexes.

Author : Allan Robertson Petersen
Publisher :
Page : pages
File Size : 47,54 MB
Release : 2012
Category :
ISBN :

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Chapter 1 provides an overview of the oxidation of methane by platinum salts known as Shilov chemistry. This includes platinum complexes used for the selective oxidation of methane to methyl bisulfate. Attention is paid to model platinum complexes that have been synthesised to explore the oxidation of methane using dioxygen as the oxidant. Chapter 2 describes two sets of tridentate N donor ligands that have been synthesised. The first set contains 6,6"-disubsthuted-2,2/:6/,2"-terpyridine ligands, of these two new ligands 6,6"-di(methylamino)-2,2/:6/,2"-terpyridine and 6,6"-dimethoxy-2,2/:6/,2"-terpyridine have been synthesised and fully characterised. The second set contains non-terpyridine tridentate ligands. The synthesis and characterisation of novel cationic platinum(II) methyl complexes bearing these ligands is described in Chapter 3. The structures of some of these complexes have been determined by X-ray crystallography. Further, the reactivity of the complexes towards dioxygen is reported and how different reactivity is imparted by the different ligands is discussed. The ability of some of these platinum(II) methyl complexes to insert dioxygen into their M-Me bonds arises from the steric interaction between the Pt-Me ligand and the substituents in the 6- and 6"-positions on the terpyridine ligand. Chapter 4 describes a study into the mechanism of the insertion of dioxygen into a Pt-Me bond. This includes deuterium labelling experiments, which led to the discovery of the exchange of methyl ligands between platinum(II) and palladium(II) centres. A mechanism for this exchange involving the formation of a MII_MII dimer is proposed. In addition, the decomposition of a palladium(II) methylperoxo complex to give an intriguing new metallacyclic hemiacetal alkoxide complex is described. A possible mechanism for the formation of this new palladium(II) complex is discussed. The synthesis and characterisation of the new compounds discussed in Chapters 2-4 are reported in Chapter 5. 4.