Rational Design of Stable and Active Palladium Nanoparticles for Heck Reaction Catalysis

Rational Design of Stable and Active Palladium Nanoparticles for Heck Reaction Catalysis PDF Author: John D. Attelah
Publisher:
ISBN:
Category : Nanostructured materials
Languages : en
Pages : 0

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Book Description
Author's abstract: Rational design of active and stable palladium nanoparticles using peptide is emerging field in nanomaterial technology. Nanoparticles are preferred as catalysts compared to their bulk counter-parts due to their large surface area-to-volume ratio making them more reactive. The use of peptide to facilitate the formation and stabilization of the inorganic nanoparticles such as palladium is desirable due to their less toxic nature, and desired products formed after the completion of the reaction. In addition, peptide is known to impart high level of control over size and shape in nanoparticles. In this work, peptide-driven fabrication of catalytically stable and reactive palladium was conducted in organic solvents and used in Heck reaction catalysis of iodobenzene and butyl acrylate to form butyl cinnamate. The use of a peptide ligands contrasts with the traditional toxic bulky phosphine ligands, which are conventionally used to stabilize and solubilize bulky palladium metal catalyst. The optimum temperature for maximum yield of butyl cinnamate was investigated in series of reactions set up from 25 to 80 °C with other reaction parameters kept constant. Heck coupling reaction is industrially important in synthesis of various pharmaceuticals We successfully conducted, characterized, and quantified the Heck coupling reaction in ethanol and DMSO at 80 °C using palladium-capped peptide nanoparticles and triethyl amine base. Different engineered and control peptides were used to fabricate palladium nanoparticles formation and for enhancing their colloidal and stability during the Heck reaction. The peptides used were engineered from the control Pd4 (TSNAVHPTLRHL) peptide, which is known to specifically bind palladium metal via the histidines at positions six and eleven. The S2 (AFILPTG) peptide, which is specific to silica, was attached at either ends of the Pd4 peptide to form S2Pd4, Pd4S2, and S2Pd4S2. The engineered peptide-capped palladium nanoparticles were investigated for their colloidal stability and catalytic activity.

Rational Design of Stable and Active Palladium Nanoparticles for Heck Reaction Catalysis

Rational Design of Stable and Active Palladium Nanoparticles for Heck Reaction Catalysis PDF Author: John D. Attelah
Publisher:
ISBN:
Category : Nanostructured materials
Languages : en
Pages : 0

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Book Description
Author's abstract: Rational design of active and stable palladium nanoparticles using peptide is emerging field in nanomaterial technology. Nanoparticles are preferred as catalysts compared to their bulk counter-parts due to their large surface area-to-volume ratio making them more reactive. The use of peptide to facilitate the formation and stabilization of the inorganic nanoparticles such as palladium is desirable due to their less toxic nature, and desired products formed after the completion of the reaction. In addition, peptide is known to impart high level of control over size and shape in nanoparticles. In this work, peptide-driven fabrication of catalytically stable and reactive palladium was conducted in organic solvents and used in Heck reaction catalysis of iodobenzene and butyl acrylate to form butyl cinnamate. The use of a peptide ligands contrasts with the traditional toxic bulky phosphine ligands, which are conventionally used to stabilize and solubilize bulky palladium metal catalyst. The optimum temperature for maximum yield of butyl cinnamate was investigated in series of reactions set up from 25 to 80 °C with other reaction parameters kept constant. Heck coupling reaction is industrially important in synthesis of various pharmaceuticals We successfully conducted, characterized, and quantified the Heck coupling reaction in ethanol and DMSO at 80 °C using palladium-capped peptide nanoparticles and triethyl amine base. Different engineered and control peptides were used to fabricate palladium nanoparticles formation and for enhancing their colloidal and stability during the Heck reaction. The peptides used were engineered from the control Pd4 (TSNAVHPTLRHL) peptide, which is known to specifically bind palladium metal via the histidines at positions six and eleven. The S2 (AFILPTG) peptide, which is specific to silica, was attached at either ends of the Pd4 peptide to form S2Pd4, Pd4S2, and S2Pd4S2. The engineered peptide-capped palladium nanoparticles were investigated for their colloidal stability and catalytic activity.

Palladium-Catalyzed Coupling Reactions

Palladium-Catalyzed Coupling Reactions PDF Author: Árpád Molnár
Publisher: John Wiley & Sons
ISBN: 3527648305
Category : Science
Languages : en
Pages : 531

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Book Description
This handbook and ready reference brings together all significant issues of practical importance in selected topics discussing recent significant achievements for interested readers in one single volume. While covering homogeneous and heterogeneous catalysis, the text is unique in focusing on such important aspects as using different reaction media, microwave techniques or catalyst recycling. It also provides a comprehensive treatment of key issues of modern-day coupling reactions having emerged and matured in recent years and emphasizes those topics that show potential for future development, such as continuous flow systems, water as a reaction medium, and catalyst immobilization, among others. With its inclusion of large-scale applications in the pharmaceutical industry, this will equally be of great interest to industrial chemists. From the contents * Palladium-Catalyzed Cross-Coupling Reactions - A General Introduction * High-turnover Heterogeneous Palladium Catalysts in Coupling Reactions: the Case of Pd Loaded on Dealuminated Y Zeolites Palladium-Catalyzed Coupling Reactions with Magnetically Separable Nanocatalysts * The Use of Ordered Porous Solids as Support Materials in Palladium-Catalyzed Cross-Coupling Reactions * Coupling Reactions Induced by Polymer-Supported Catalysts * Coupling Reactions in Ionic Liquids * Cross-Coupling Reactions in Aqueous Media * Microwave-Assisted Synthesis in C-C and C-Heteroatom Coupling Reactions * Catalyst Recycling in Palladium-Catalyzed Carbon-Carbon Coupling Reactions * Nature of the True Catalytic Species in Carbon-Carbon Coupling Reactions with * Heterogeneous Palladium Precatalysts * Coupling Reactions in Continuous Flow Systems * Large-Scale Applications of Palladium-Catalyzed Couplings in the Pharmaceutical Industry

The Mizoroki-Heck Reaction

The Mizoroki-Heck Reaction PDF Author: Martin Oestreich
Publisher: John Wiley & Sons
ISBN: 9780470716069
Category : Science
Languages : en
Pages : 608

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Book Description
Exploring the importance of Richard F. Heck’s carbon coupling reaction, this book highlights the subject of the 2010 Nobel Prize in Chemistry for palladium-catalyzed cross couplings in organic synthesis, and includes a foreword from Nobel Prize winner Richard F. Heck. The Mizoroki-Heck reaction is a palladium-catalyzed carbon–carbon bond forming process which is widely used in organic and organometallic synthesis. It has seen increasing use in the past decade as chemists look for strategies enabling the controlled construction of complex carbon skeletons. The Mizoroki-Heck Reaction is the first dedicated volume on this important reaction, including topics on: mechanisms of the Mizoroki-Heck reaction intermolecular Mizoroki-Heck reactions focus on regioselectivity and product outcome in organic synthesis waste-minimized Mizoroki-Heck reactions intramolecular Mizoroki-Heck reactions formation of heterocycles chelation-controlled Mizoroki-Heck reactions the Mizoroki-Heck reaction in domino processes oxidative heck-type reactions (Fujiwara-Moritani reactions) Mizoroki-Heck reactions with metals other than palladium ligand design for intermolecular asymmetric Mizoroki-Heck reactions intramolecular enantioselective Mizoroki-Heck reactions desymmetrizing Mizoroki-Heck reactions applications in combinatorial and solid phase syntheses, and the development of modern solvent systems and reaction techniques the asymmetric intramolecular Mizoroki-Heck reaction in natural product total synthesis Several chapters are devoted to asymmetric Heck reactions with particular focus on the construction of otherwise difficult-to-obtain sterically congested tertiary and quaternary carbons. Industrial and academic applications are highlighted in the final section. The Mizoroki-Heck Reaction will find a place on the bookshelves of any organic or organometallic chemist. “I am convinced that this book will rapidly become the most important reference text for research chemists in academia and industry who seek orientation in the rapidly growing and – for the layman – confusing field described as the “’Mizoroki–Heck reaction’.” (Synthesis, March 2010)

Ordinary North-Carolinese, Or "I Had Rather Stay Than to Go with You."

Ordinary North-Carolinese, Or Author: Charles Alphonso Smith
Publisher:
ISBN:
Category : English language
Languages : en
Pages : 5

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Book Description


Nanometal Catalysis in Organic Synthesis

Nanometal Catalysis in Organic Synthesis PDF Author: Ming Bao
Publisher: Springer Nature
ISBN: 981974573X
Category :
Languages : en
Pages : 228

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Book Description


Metal Organic Frameworks as Heterogeneous Catalysts

Metal Organic Frameworks as Heterogeneous Catalysts PDF Author: Francesc X. Llabrés i Xamena
Publisher: Royal Society of Chemistry
ISBN: 1849735727
Category : Science
Languages : en
Pages : 446

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Book Description
This book examines the latest research and discovery in the use of MOFs in catalysis, highlighting the extent to which these materials have been embraced by the community.

Artificial Metalloenzymes and MetalloDNAzymes in Catalysis

Artificial Metalloenzymes and MetalloDNAzymes in Catalysis PDF Author: Montserrat Diéguez
Publisher: John Wiley & Sons
ISBN: 3527804072
Category : Technology & Engineering
Languages : en
Pages : 431

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Book Description
An important reference for researchers in the field of metal-enzyme hybrid catalysis Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a comprehensive review of the most current strategies, developed over recent decades, for the design, synthesis, and optimization of these hybrid catalysts as well as material about their application. The contributors—noted experts in the field—present information on the preparation, characterization, and optimization of artificial metalloenzymes in a timely and authoritative manner. The authors present a thorough examination of this interesting new platform for catalysis that combines the excellent selective recognition/binding properties of enzymes with transition metal catalysts. The text includes information on the various applications of metal-enzyme hybrid catalysts for novel reactions, offers insights into the latest advances in the field, and contains an informative perspective on the future: Explores the development of artificial metalloenzymes, the modern and strongly evolving research field on the verge of industrial application Contains a comprehensive reference to the research area of metal-enzyme hybrid catalysis that has experienced tremendous growth in recent years Includes contributions from leading researchers in the field Shows how this new catalysis combines the selective recognition/binding properties of enzymes with transition metal catalysts Written for catalytic chemists, bioinorganic chemists, biochemists, and organic chemists, Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a unique reference to the fundamentals, concepts, applications, and the most recent developments for more efficient and sustainable synthesis.

Metal Nanoparticles for Catalysis

Metal Nanoparticles for Catalysis PDF Author: Franklin Tao
Publisher: Royal Society of Chemistry
ISBN: 1782621032
Category : Technology & Engineering
Languages : en
Pages : 285

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Book Description
Catalysis is a central topic in chemical transformation and energy conversion. Thanks to the spectacular achievements of colloidal chemistry and the synthesis of nanomaterials over the last two decades, there have also been significant advances in nanoparticle catalysis. Catalysis on different metal nanostructures with well-defined structures and composition has been extensively studied. Metal nanocrystals synthesized with colloidal chemistry exhibit different catalytic performances in contrast to metal nanoparticles prepared with impregnation or deposition precipitation. Additionally, theoretical approaches in predicting catalysis performance and understanding catalytic mechanism on these metal nanocatalysts have made significant progress. Metal Nanoparticles for Catalysis is a comprehensive text on catalysis on Nanoparticles, looking at both their synthesis and applications. Chapter topics include nanoreactor catalysis; Pd nanoparticles in C-C coupling reactions; metal salt-based gold nanocatalysts; theoretical insights into metal nanocatalysts; and nanoparticle mediated clock reaction. This book bridges the gap between nanomaterials synthesis and characterization, and catalysis. As such, this text will be a valuable resource for postgraduate students and researchers in these exciting fields.

Catalyst Separation, Recovery and Recycling

Catalyst Separation, Recovery and Recycling PDF Author: David J. Cole-Hamilton
Publisher: Springer Science & Business Media
ISBN: 9781402040863
Category : Science
Languages : en
Pages : 270

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Book Description
This book looks at new ways of tackling the problem of separating reaction products from homogeneous catalytic solutions. The new processes involve low leaching supported catalysts, soluble supports such as polymers and dendrimers and unusual solvents such as water, fluorinated organics, ionic liquids and supercritical fluids. The advantages of the different possibilities are discussed alongside suggestions for further research that will be required for commercialisation. Unlike other books, in addition to the chemistry involved, the book looks at the process design that would be required to bring the new approaches to fruition. Comparisons are given with existing processes that have already been successfully applied and examples are given where these approaches are not suitable. The book includes: - New processes for the separation of products from solutions containing homogeneous catalysts - Catalysts on insoluble or soluble supports – fixed bed catalysts - continuous flow or ultrafiltration - Biphasic systems: water - organic, fluorous - organic, ionic liquid – organic, supercritical fluids (monophasic or biphasic with water, organic or ionic liquid) - Comparisons with current processes involving atmospheric or low temperature distillation - Consideration of Chemistry and Process Design - Advantages and disadvantages of each process exposed - Consideration of what else is need for commercialisation

Tailored Metal Nanoparticles for Selective Catalysis

Tailored Metal Nanoparticles for Selective Catalysis PDF Author: Christine V. Gaskell
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The development of clean, sustainable chemical processes is a key priority towards meeting the growing demand for synthetic functional chemicals, while balancing rapidly depleting natural resources. The selective oxidation (selox) of crotyl alcohol to crotonaldehyde and the selective hydrogenation of benzyl cyanide to phenylethylamine are two specific systems for which, it is proposed, new heterogeneous catalysts and deeper mechanistic insight will improve. In this thesis the rational design of palladium catalysts is investigated for these systems, via synthesis of palladium nanoparticles with tailored morphology and palladium-gold nanoparticles with tuneable surface composition. Pd icosahedra, nanorods and nanocubes were synthesised and characterised extensively to confirm the size and morphology of the nanoparticles. Pd icosahedra are revealed to be three times more active for crotyl alcohol selox than the nanocubes, and ten times faster than the nanorods, while maintaining good selectivity. An Au-shell, Pd-core structure was synthesised, progressively annealed to induce alloying and characterised using various in situ spectroscopies. Surface Au was found to enhance crotyl alcohol selox activity and selectivity towards crotonaldehyde, in accordance with model predictions. An optimum crotonaldehyde yield was obtained for an Au40Pd60 surface alloy. By employing in situ and time-resolved spectroscopies the active site of Pd selox catalysts is examined, and the role of oxygen in this system and the catalyst's kinetic behaviour is defined. Reversible redox cycling of the catalyst dependent on its environment was observed, and it was possible to identify PdOx as the active catalytic species responsible for selectively oxidising crotyl alcohol to crotonaldehyde, with high temperatures suppressing catalytic selectivity. Systematic characterisation of an industrial carbon supported Pd catalyst, used in nitrile hydrogenation, reveals potential sources of deactivation including surface poisoning by CN species. Solutions to improve catalyst performance are proposed using the knowledge acquired from the nanoparticle catalysts' studies.