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Book The Synthesis of Dinuclear Molybdenum Complexes and Catalytic Reactions of Molybdenum Sulfido Complexes with Hydrogen

Download or read book The Synthesis of Dinuclear Molybdenum Complexes and Catalytic Reactions of Molybdenum Sulfido Complexes with Hydrogen written by Rohini T. Mehta Vohra and published by . This book was released on 1982 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Recent Advances in Hydride Chemistry

Download or read book Recent Advances in Hydride Chemistry written by Maurizio Peruzzini and published by Elsevier. This book was released on 2002-01-30 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has been conceived to collect the most important recent advances in all areas of hydride chemistry research, including chemical reactivity, instrumental investigation, theory, and applications in the areas of catalysis, biochemistry and materials science. Many of the chapters have been written by the plenary lecturers of the EURO-Hydrides 2000 conference, but other leading scientists in this field have also been invited to contribute. The first part of the book focuses on the chemistry and catalysis of transition metal hydrides. Another block of chapters illustrates the most recent advances in the application of instrumental techniques to the study of the properties and reactivity of hydride compounds. The final part of the book illustrates the relevance of metal-hydrogen bonds in biochemistry and materials science. All of the chapters of this book have been evaluated by independent reviewers.

Book Synthesis and Studies of Mo and W Complexes for 2N Reduction

Download or read book Synthesis and Studies of Mo and W Complexes for 2N Reduction written by Jia Min Chin and published by . This book was released on 2010 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of monopyrroletriamine ligands [Arpyr(Ar')2]H3 of the form ArC4H2NHCH2N(CH2CH2NHAr')2 (Ar = 2,4,6-mesityl (Mes), 2,4,6-triisopropylphenyl (TRIP); Ar' = C6F5, 2-tolyl (o-tol), naphthyl, 3,5-(2,4,6-triisopropylphenyl)phenyl (HIPT), 3,5- dimethylphenyl, 3,5-di-tert-butylphenyl were synthesized. [Mespyr(C6F5)2]MoCl, ([Mespyr(C6F5)2]Mo = MesitylC4H2NCH2N(CH2CH2NC6F5)2) was prepared by reaction of [Mespyr(C6F5)2]H3 with MoCl4(THF)2 and base and [Mespyr(3,5-t-Bu)2]MoCl and [Mespyr(3,5- Me)2]MoCl (3,5-t-Bu=3,5-di-tert-butylphenyl, Me = 3,5-dimethylphenyl) were synthesized likewise. All three monochlorides are paramagnetic. [Mespyr(C6F5)2]MoNMe2, [[Mespyr(otol) 2]MoNMe2, [Mespyr(3,5-t-Bu)2]MoNMe2, [Mespyr(3,5-Me)2]MoNMe2 were synthesized by reaction of the ligands with Mo(NMe2)4. The resulting compounds are diamagnetic and range in color from teal blue to emerald green. These low spin monodimethylamide complexes exist in rapid equilibria with their high spin forms. [Mespyr(C6F5)2]MoN and [Mespyr(3,5-t-Bu)2]MoN were synthesized by reaction of their respective monochlorides with NaN3 and are yellow diamagnetic species. Reaction of [Mespyr(3,5-t-Bu)2]MoN with Et3OBF4 leads to {[Mespyr(3,5- t-Bu)2]MoNEt}BF4, also a diamagnetic yellow species. [Mespyr(C6F5)2]MoOTf is synthesized by the reaction of [Mespyr(C6F5)2]MoCl with AgOTf. Reduction of [Mespyr(3,5-t-Bu)2]MoCl with Na under N2 led to [Mespyr(3,5-t-Bu)2]MoNNNa(THF)x, several species with varying numbers of THF coordination, x. A single species can be obtained when [Mespyr(3,5-t- Bu)2]MoNNNa(THF)x is reacted with either NBu4Cl or 15-crown-5 ether to yield purple green 4 {[Mespyr(3,5-t-Bu)2]MoNN}NBu4 or [Mespyr(3,5-t-Bu)2]MoNNNa(15-c-5). All the diazenide species are diamagnetic. Oxidation of the diazenide with AgOTf yields [Mespyr(3,5-t- Bu)2]Mo(N2). [Mespyr(3,5-t-Bu)2]Mo(CO) is synthesized by exposure of [Mespyr(3,5-t- Bu)2]Mo(N2) to CO. Reaction of [Mespyr(3,5-t-Bu)2]MoCl with NaBPh4 and NH3 yields {[Mespyr(3,5-t-Bu)2]Mo(NH3)}BPh4. Catalytic runs employing [Mespyr(3,5-t-Bu)2]MoN as the catalyst yielded one equivalent of NH3. A triamidoamine ligand [(HIPTNCH2CH2CH2)3N]3- was synthesized and metalated with MoCl4(THF)2 to produce [(HIPTNCH2CH2CH2)3N]MoCl ([HIPTtrpn]MoCl). Reduction of [HIPTtrpn]MoCl by KC8 under an atmosphere of dinitrogen leads to the green species [HIPTtrpn]MoNNK which can be oxidized by ZnCl2(dioxane) to produce [HIPTtrpn]Mo(N2). Other complexes synthesized include {[HIPTtrpn]Mo(NH3)}+ salts and [HIPTtrpn]Mo(CO). Xray studies were carried out on [HIPTtrpn]MoN and {[HIPTtrpn]Mo(NH3)}BAr'4. This system is not catalytic for the reduction of dinitrogen to ammonia and studies were carried out to elucidate the reasons. Oxidation studies were carried out on [HIPTN3N]Mo(N2) and [HIPTN3N]W(N2) ([HIPTN3N] = [(HIPTNCH2CH2)3N]3- ). The rate of conversion of [HIPTN3N]Mo(NH3) to [HIPTN3N]Mo(N2) was studied and found to be increased in the presence of BPh3. [HIPTN3N]Mo(N2) conversion to [HIPTN3N]Mo(CO) was found to be dependent on CO pressure. Protonation studies of [HIPTN3N]Mo(N2) were also carried out. Studies of [HIPTN3N]MoNNH decomposition showed that decomposition is not base-catalyzed. [HIPTN3N]W(CO) was synthesized by exposure of [HIPTN3N]W(N2) to CO. It is a green, paramagnetic compound and its use as a standard (for determining relative concentrations of other compounds in the IR sample) in IR spectroscopic studies appears to be promising. [HIPTN3N]MoCNH2 was synthesized by addition of acid and reducing agent to [HIPTN3N]MoCN and is a yellow, diamagnetic compound. Two triamidophosphine ligands, triHIPTamine and tri-n-Buamine were synthesized. Metalation of Zr(NMe2)4 with these ligands leads to formation of pn3HIPTZrNMe2 and pn3-n- BuZrNMe2, both diamagnetic, pale yellow complexes.

Book Molybdenum Pincer Complexes

Download or read book Molybdenum Pincer Complexes written by Thomas Leischner and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The present thesis describes the synthesis of novel molybdenum pincer complexes and their application as catalysts for the homogeneous hydrogenation of unsaturated organic molecules. PNP-type pincer ligands with aliphatic backbones were a focal point in this respect. A synthetic methodology for the preparation of related organometallic compounds was developed, giving access to diverse Mo(0), Mo(I) and Mo(II) compounds. The reported complexes were subsequently applied for the catalytic hydrogenation of ketones, styrenes, N-methylated formanilides as well as aromatic and aliphatic nitriles.eng

Book Synthesis Characterization and Catalytic Activity of Molybdenum VI Di and Monooxo Aryloxides

Download or read book Synthesis Characterization and Catalytic Activity of Molybdenum VI Di and Monooxo Aryloxides written by Mauricio Quiroz-Guzmán and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of molybdenum is immensely rich and diverse. Molybdenum is essential for life, and has many applications in industry. The first chapter offers a general perspective of the chemistry of molybdenum in high oxidation states dominated by diverse oxo species, such as the MoO22+ and MoO4+ units that are focus of my research. I describe the importance of MoO22+ complexes as models for the active sites of oxo transfer molybdoenzymes (e.g. DMSO oxidase) and for industrial heterogeneous transformation such as the SOHIO process (one of our ultimate goals). I also outline the importance of MoO4+ complexes as procatalysts for metathesis polymerization and as models of deoxygenated active sites of MoO22+ oxygen catalysts that have triggered our interest. The second chapter introduces the synthesis and full characterization of 4-, 5- and 6-coordinated MoO2(OAr)2L0-1 complexes with bulky aryloxide ligands, starting from the MoO2Cl2 or MoO2Cl2(DMF)2 precursors. Steric and electronic modifications in the aryloxide moieties were performed in order to understand their effect in the final structure and yields of the synthesized complexes. The nature and mechanism of formation of the radical species detected in their synthesis is proposed. The third chapter presents the facile synthesis of varios MoO(OAr)4-nCln complexes starting from the MoO2Cl2 precursor. Their mechanism of formation is proposed and the supporting evidence for this new reaction is provided. Steric and electronic modifications in the aryloxide moieties were used to study their structural and electronic effects in the MoO4+ complexes. The fourth chapter outlines the synthesis of Mo(VI) monooxo bisphenoxides with a characteristic cis-chloro cis-bisphoxide arrangement around the MoO4+ unit. Electronic and steric modifications in the bisphenoxide rings were done to determine their effect in the structure and reactivity of the final complexes. The fifth chapter introduces the application of the synthesized MoO(OAr)4-nCln and MoO(bisphenoxides)2Cl2 complexes as procatalysts for olefin metathesis polymerization of norbornene. The correlation between structure and reactivity of the procatalyst is discussed.

Book Transition Metal Dinitrogen Complexes

Download or read book Transition Metal Dinitrogen Complexes written by Yoshiaki Nishibayashi and published by John Wiley & Sons. This book was released on 2019-05-06 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive book that explores nitrogen fixation by using transition metal-dinitrogen complexes Nitrogen fixation is one of the most prominent fields of research in chemistry. This book puts the focus on the development of catalytic ammonia formation from nitrogen gas under ambient reaction conditions that has been recently repowered by some research groups. With contributions from noted experts in the field, Transition Metal-Dinitrogen Complexes offers an important guide and comprehensive resource to the most recent research and developments on the topic of nitrogen fixation by using transition metal-dinitrogen. The book is filled with the information needed to understand the synthesis of transition metal-dinitrogen complexes and their reactivity. This important book: -Offers a resource for understanding nitrogen fixation chemistry that is essential for explosives, pharmaceuticals, dyes, and all forms of life -Includes the information needed for anyone interested in the field of nitrogen fixation by using transition metal-dinitrogen complexes -Contains state-of-the-art research on synthesis of transition metal-dinitrogen complexes and their reactivity in nitrogen fixation -Incorporates contributions from well-known specialists and experts with an editor who is an innovator in the field of dinitrogen chemistry Written for chemists and scientists with an interest in nitrogen fixation, Transition Metal-Dinitrogen Complexes is a must-have resource to the burgeoning field of nitrogen fixation by using transition metal-dinitrogen complexes.

Book Synthesis of Molybdenum Complexes

Download or read book Synthesis of Molybdenum Complexes written by Judith Sabina Schreiber and published by . This book was released on 1977 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Synthesis and Reactions of Molybdenum II and Tungsten II Alkyne Complexes

Download or read book The Synthesis and Reactions of Molybdenum II and Tungsten II Alkyne Complexes written by Elaine M. Armstrong and published by . This book was released on 1989 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Reactivity of Molybdenum Organometallic Complexes Supported by Amide Ligands

Download or read book Synthesis and Reactivity of Molybdenum Organometallic Complexes Supported by Amide Ligands written by Adam Scott Hock and published by . This book was released on 2007 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) Chapter 4. Reactivity of Molybdenum Imido Alkylidene Bis(pyrrolyl) Complexes. The Lewis amphoteric nature of the bis(pyrrolyl) complexes reported in chapter 3 is examined by demonstrating that these complexes react with both trimethylphosphine (at the molybdenum center) and B(C6Fs)3 (at a q5 pyrrolyl nitrogen). A structure of a trimethylphosphine adduct is reported. The bis(pyrrolyl) complexes are found to serve as excellent precursors for the in situ generation of olefin metathesis catalysts at room temperature and millimolar concentration. Furthermore, catalysts not accessible via traditional routes may now be accessed from bis(pyrrolyl) precursors. The bis(pyrrolyl) complexes also react with simple olefins such as ethylene and isobutylene to yield what are proposed to be a bimetallic dimer [Mo(NAr)(NC4H4)2]2 and a 2-propylidene complex via olefin metathesis. The impact of in situ synthesis on syn and anti isomer ratios is discussed as is reactivity with protic reagents other than alcohols.

Book Transition Metal Sulphides

    Transition Metal Sulphides

    Book Details:
  • Author : Th. Weber
  • Publisher : Springer Science & Business Media
  • Release : 2013-06-29
  • ISBN : 9401735778
  • Pages : 357 pages

Download or read book Transition Metal Sulphides written by Th. Weber and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrotreating catalysis with transition metal sulphides is one of the most important areas of industrial heterogeneous catalysis. The present book deals with the chemical and catalytic aspects of transition metal sulphides, focusing on their use in hydrotreating catalysis. The book¿s 12 chapters present reviews of solid-state, coordination and organometallic chemistry, surface science and spectroscopic studies, quantum chemical calculations, catalytic studies with model and real catalysts, as well as refinery processes. A presentation of state-of-the-art background to pertinent work in the field. Can be used as an introduction to the chemical and catalytic properties of transition metal sulphides as well as an advanced level reference.

Book Molybdenum Alkylidene Complexes

Download or read book Molybdenum Alkylidene Complexes written by Tatiana Pilyugina and published by . This book was released on 2007 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) Chapter 3. Reactions of Mo Bispyrrolide Complexes with Enantiomerically Pure Diols: In Situ Catalyst Generation and Studies of Olefin Metathesis Reactions In the Fume Hood. Reactions of bispyrrolide molybdenum complexes Mo(NAd)(CHCMe2Ph)(pyr)2 and Mo(N-2-6-i-Pr2C6H3)(CHCMe2Ph)(pyr)2 with (R)-BiphenH2, and (R)-Benz2BitetH2 were examined (pyr = C4H4N, Benz2BitetH2 = 3,3'-dibenzhydryl-5,5',6,6',7,7',8,8'-octahydro-1,1'- binaphthyl-2,2'-diol). The resulting in situ generated catalysts were studied in three olefin metathesis reactions. These systems were found to be as active and enantioselective as the analogous isolated complexes. When the stock solutions of Mo(NAd)(CHCMe2Ph)(pyr)2, Mo(N- 2,6-i-Pr2C6H3)(CHCMe2Ph)(pyr)2, (R)-BiphenH2, and (R)-Benz2BitetH2 were stored in the fume hood over a period of one month, the in situ prepared catalysts were determined to be nearly identical in terms of their catalytic properties to the catalysts generated in situ in the glovebox.