Novel Chiral Di-N-heterocyclic Carbene and Hybrid Phosphine-N-heterocyclic Carbene Ligands and Their Application to Transition Metal Mediated Asymmetric Catalysis

Novel Chiral Di-N-heterocyclic Carbene and Hybrid Phosphine-N-heterocyclic Carbene Ligands and Their Application to Transition Metal Mediated Asymmetric Catalysis PDF Author:
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ISBN:
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Languages : en
Pages : 334

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Chiral Phosphorous Based Ligands in Earth-Abundant Transition Metal Catalysis

Chiral Phosphorous Based Ligands in Earth-Abundant Transition Metal Catalysis PDF Author: Junliang Zhang
Publisher: Elsevier
ISBN: 0323852262
Category : Science
Languages : en
Pages : 322

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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

Functionalised N-Heterocyclic Carbene Complexes

Functionalised N-Heterocyclic Carbene Complexes PDF Author: Olaf Kühl
Publisher: Wiley
ISBN: 9780470712153
Category : Science
Languages : en
Pages : 364

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N-heterocyclic carbenes (NHCs) have found increasing use as reagents for a range of organic transformations and in asymmetric organocatalysis. The performance of these molecules can be improved and tuned by functionalisation. Functionalised carbenes can anchor free carbenes to the metal site, introduce hemilability, provide a means to immobilise transition metal carbene catalysts, introduce chirality, provide a chelate ligand or bridge two metal centres. NHC can be attached to carbohydrates and campher, derived from amino acids and purines, they can be used as organocatalysts mimicking vitamin B1 or as weak “solvent” donors in lanthanide chemistry. Functionalised N-Heterocyclic Carbene Complexes describes major trends in functionalised NHC ligands, aiming to assist readers in their attempts to develop and apply their own functionalised carbenes. After an introduction to the chemistry and behaviour of NHC, the book gives a detailed description of functionalised carbenes and their complexes according to a range of functional groups, each with a discussion of the synthetic route, structure, stability and performance. Functionalised N-Heterocyclic Carbene Complexes is an essential guide to fine-tuning this important class of compounds for practitioners, researchers and advanced students working in synthetic organometallic and organic chemistry and catalysis.

New Chiral N-heterocyclic Carbene-imine Ligands and Their Application to Asymmetric Catalysis

New Chiral N-heterocyclic Carbene-imine Ligands and Their Application to Asymmetric Catalysis PDF Author: Ludovic Grkegoire Bonnet
Publisher:
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Category :
Languages : en
Pages :

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Chiral Iron Pyridine Complexes and Ruthenium Complexes with N-Heterocyclic Carbene and Macrocyclic (N, O) Donor Atom Ligands

Chiral Iron Pyridine Complexes and Ruthenium Complexes with N-Heterocyclic Carbene and Macrocyclic (N, O) Donor Atom Ligands PDF Author: Kar-Yee Lam
Publisher:
ISBN: 9781361034422
Category :
Languages : en
Pages :

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This dissertation, "Chiral Iron Pyridine Complexes and Ruthenium Complexes With N-heterocyclic Carbene and Macrocyclic (N, O) Donor Atom Ligands: Synthesis, Catalytic Activity and Biological Studies" by Kar-yee, Lam, 林嘉儀, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled CHIRAL IRON PYRIDINE COMPLEXES AND RUTHENIUM COMPLEXES WITH N-HETEROCYCLIC CARBENE AND MACROCYCLIC(N, O) DONOR ATOM LIGANDS: SYNTHESIS, CATALYTIC ACTIVITY AND BIOLOGICAL STUDIES Submitted by Lam Kar Yee For the degree of Doctor of Philosophy at The University of Hong Kong in April 2016 Transition metal complexes are widely applied as catalysts for organic transformation reactions such as the oxygen atom and nitrene transfer reactions and there is a growing interest to develop the medicinal applications of transition metal complexes. The studies of reactive metal-oxo and metal-nitrene intermediates are important in probing the underlying reaction mechanisms. This thesis is comprised of three main parts. In the first part, iron complexes with chiral pyridine ligands, such as 4′,6-disubstituted 2,2′ 6′,2″-terpyridine (NNN ) and 4′,6,6″-trisubstituted 2,2′ 6′,2″''-terpyridine (NNN ), were studied for their catalytic activities in asymmetric epoxidation, aziridination, amidation and sulfimidation reactions. The Fe-NNN complex catalyzed intermolecular nitrene transfer/CN bond formation reactions of styrenes with PhINTs in moderate product yields. For the asymmetric intramolecular amidation, the Fe-NNN complex can catalyze intramolecular C-N bond formation using PhI(OAc) as oxidant to form five- or six-membered ring products. The highest product yield obtained was 91 %. The complete conversion of para-substituted phenyl methyl sulfides to corresponding sulfimides was observed by using the Fe-NNN 1 2 complex as catalyst. Both the Fe-NNN and Fe-NNN complexes catalyzed asymmetric epoxidation of styrene using PhIO as oxidant at 0 C. The reaction intermediates of the nitrene/oxygen transfer reactions were studied by ESI-MS and high-valent iron-ligand multiple bonded species are proposed to be the reaction intermediates. In the second part, ruthenium pincer N-heterocyclic carbene (CNC) complexes were prepared and characterized by spectroscopic means and X-ray crystallography. II 2+ Complex [Ru (CNC)(bpy)(MeCN)], in which the CNC ligand adopts a fac-coordination mode and contains reactive CH bond of bridging methylene group, was found to react with PhINTs to result in the formation of a new CN bond and cleavage of one existing NC(methylene) bond of the CNC ligand, as revealed by X-ray crystal structure determination of the ruthenium complex product. The reaction 2+ of [Ru(CNC)(bpy)(MeCN)] with PhINTs was monitored by ESI-MS, UV-vis, and NMR spectroscopy; a paramagnetic Ru(III)-amido complex was isolated, which apparently resulted from intramolecular imido/nitrene CH insertion of a Ru(IV)-imido/nitrene intermediate and was found to undergo the observed CN bond cleavage. Such type of CN bond cleavage induced by metal-mediated imido/nitrene insertion is unprecedented in literature. The final part of this thesis is the study of the anti-angiogenic and anti-metastatic properties of the ruthenium complexes. Ruthenium complexes with different oxidation states (+2 and +3) and ligands (pincer NHC and macrocyclic (N, O) donor atom ligands) were examined for their cytotoxicity and anti-angiogenesis activity. III Among the complexes studied, [Ru (N O )Cl ]Cl (Ru-1) displays promising 2 2 2 inhibi

N-heterocyclic Carbenes and Their Application as Ligands for Transition Metal Mediated Synthesis

N-heterocyclic Carbenes and Their Application as Ligands for Transition Metal Mediated Synthesis PDF Author:
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ISBN:
Category :
Languages : en
Pages :

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N-heterocyclic Carbene Ligands for Iridium-catalysed Asymmetric Hydrogenation

N-heterocyclic Carbene Ligands for Iridium-catalysed Asymmetric Hydrogenation PDF Author: Steve Nanchen
Publisher: Cuvillier Verlag
ISBN: 3865377157
Category :
Languages : en
Pages : 227

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New Chiral Di-n-heterocyclic Carbene Ligands and Their Application in Enantioselective Hydrogenation, Hydroformylation and 1,4-conjugate Addition Reactions. a Study Toward Rational Development of Di-n-heterocyclic Carbene Complexes in Enantioselective Catalysis

New Chiral Di-n-heterocyclic Carbene Ligands and Their Application in Enantioselective Hydrogenation, Hydroformylation and 1,4-conjugate Addition Reactions. a Study Toward Rational Development of Di-n-heterocyclic Carbene Complexes in Enantioselective Catalysis PDF Author: Matthew Stephen Jeletic
Publisher:
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Category :
Languages : en
Pages :

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We finally present catalytic hydrogenation, hydrogen transfer, hydrosilylation, hydroformylation and 1,4-conjugate addition reactions. The % e.e. for hydrogenation ranged from 0-10%. for the reactions involving hydrogen. These results are attributable to either reductive elimination of the diNHC from the metal center, high temperatures necessary to achieve reaction conversion, or the inherent flexibility of the DEAM ligands. The Pd(diNHC) complexes achieved better selectivity in 1,4-conjugate addition reactions (0-67% e.e.).

Synthesis of New PCP N-heterocyclic Carbene Ligands, Complexes with Transition Metals, and Application in Asymmetric Catalysis

Synthesis of New PCP N-heterocyclic Carbene Ligands, Complexes with Transition Metals, and Application in Asymmetric Catalysis PDF Author: Sebastian Martin Gischig
Publisher:
ISBN:
Category :
Languages : en
Pages : 372

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Transition Metal Catalyzed Enantioselective Allylic Substitution in Organic Synthesis

Transition Metal Catalyzed Enantioselective Allylic Substitution in Organic Synthesis PDF Author: Uli Kazmaier
Publisher: Springer
ISBN: 364222749X
Category : Science
Languages : en
Pages : 354

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Giovanni Poli, Guillaume Prestat, Frédéric Liron, Claire Kammerer-Pentier: Selectivity in Palladium Catalyzed Allylic Substitution.- Jonatan Kleimark and Per-Ola Norrby: Computational Insights into Palladium-mediated Allylic Substitution Reactions.- Ludovic Milhau, Patrick J. Guiry: Palladium-catalyzed enantioselective allylic substitution.- Wen-Bo Liu, Ji-Bao Xia, Shu-Li You: Iridium-Catalyzed Asymmetric Allylic Substitutions.- Christina Moberg: Molybdenum- and Tungsten-Catalyzed Enantioselective Allylic Substitutions.- Jean-Baptiste Langlois, Alexandre Alexakis: Copper-catalyzed enantioselective allylic substitution.- Jeanne-Marie Begouin, Johannes E. M. N. Klein, Daniel Weickmann, B. Plietker: Allylic Substitutions Catalyzed by Miscellaneous Metals.- Barry M. Trost, Matthew L. Crawley: Enantioselective Allylic Substitutions in Natural Product Synthesis.