Download or read book TRANSITION METAL CATALYZED CARBON CARBON AND CARBON NITROGEN BOND FORMATION AND ASYMMETRIC CATALYSIS WITH BISOXAZOLIDINE LIGANDS written by Hanhui Xu and published by . This book was released on 2012 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Palladium-phosphinous acids and chlorophosphine analogues have attracted increasing interest due to their high catalytic activity in various organic transformations, long shelf-life and facile handling. In this thesis, it is reported that these catalysts are very useful in Negishi cross-couplings of aryl or acyl halides with aliphatic and aromatic organozinc reagents. Similarly, palladium-phosphinous acids were employed in the formation of sterically hindered biaryls exhibiting at least two ortho substituents from aryl halides and aryl Grignard reagents.

Download or read book Catalyzed Carbon Heteroatom Bond Formation written by Andrei K. Yudin and published by John Wiley & Sons. This book was released on 2010-12-01 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an experienced editor widely acclaimed within the scientific community, this book covers everything fromo9xygen to nitrogen functionalities. From the contents: Palladium-Catalyzed Syntheses of Five-Member Saturated Heterocyclic and of Aromatic Heterodynes Palladium-Catalysis for Oxidative 1, 2-Difunctionalization of Alkenes Rhodium-Catalyzed Amination of C-H-Bonds Carbon-Heteroatom Bond Formation by RH(I)-Catalyzed Ring-Opening Reactions Transition Metal-Catalyzed Synthesis of Lactones and of Monocyclic and Fused Five-Membered Aromatic heterocycles the Formation of Carbon-Sulfur and Carbon-Selenium bonds by Substitution and Addition reactions catalyzed by Transition Metal Complexes New Reactions of Copper Acetylides Gold Catalyzed Addition of Nitrogen, Sulfur and Oxygen Nucleophiles to C-C Multiple Bonds. The result is an indispensable source of information for the Strategic Planning of the Synthetic routes for organic, catalytic and medicinal chemists, as well as chemists in industry.

Download or read book New Reactivity and Selectivity in Transition Metal catalyzed C C and C N Bond Forming Processes written by and published by . This book was released on 2015 with total page 881 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part I. Palladium-Catalyzed Carbon-Carbon Bond Forming Cross-Couplings Chapter 1. Ligand-Controlled Palladium-Catalyzed Regiodivergent Suzuki-Miyaura Cross-Coupling of Allylboronates and Aryl Halides An orthogonal set of catalyst systems based on the use of two biarylphosphine ligands has been developed for the Suzuki-Miyaura coupling of 3,3-disubstituted and 3-monosubstituted allylboronates with (hetero)aryl halides. These methods allow for the regiodivergent preparation of either the ct- or the [gamma]-isomeric coupling product with high levels of site selectivity using a common allylboron building block. Preliminary investigations have demonstrated the feasibility of an enantioselective variant for the [gamma]-selective cross-coupling using chiral monodentate biarylphosphine ligands. Chapter 2. Palladium-Catalyzed Completely Linear-Selective Negishi Coupling of 3,3-Disubstituted Organozinc Reagents with Aryl and Vinyl Electrophiles A palladium-catalyzed general and completely linear-selective Negishi coupling of 3,3- disubstituted allyl organozinc reagents with (hetero)aryl and vinyl electrophiles has been developed. This method provided an effective means for accessing highly functionalized aromatic and heteroaromatic compounds bearing prenyl-type side chains. The utility of the current protocol was further illustrated in the concise synthesis of the anti-HIV natural product siamenol. Chapter 3. Palladium-Catalyzed Highly Selective Negishi Cross-Coupling of Secondary Alkylzinc Reagents with Aryl and Heteroaryl Halides The palladium-catalyzed Negishi cross-coupling of secondary alkylzinc reagents and heteroaryl halides with high levels of regioisomeric retention has been described. The development of a series of biarylphosphine ligands has led to the identification of an improved catalyst for the coupling of electron-deficient heterocyclic substrates. Preparation and characterization of oxidative addition complex (L)Pd(Ar)(Br) provided insight into the unique reactivity of palladium catalysts based on CPhos-type biarylphosphine ligands in facilitating challenging reductive elimination processes. Chapter 4. Mechanistic Studies on the Aryl-Trifluoromethyl Reductive Elimination from Pd(II) Complexes Based on Biarylphosphine Ligands A series of monoligated (L)Pd(Ar)(CF3) (L = dialkyl biarylphosphine) have been prepared and studied in an effort to shed light on the mechanism of the aryl-trifluoromethyl reductive elimination from these systems. Combined experimental and computational investigations revealed unique reactivity and binding modes of (L)Pd(Ar)(CF3) complexes derived from BrettPhos-type biarylphosphines. In contrast to a variety of C-C and C-heteroatom bond forming reductive eliminations, kinetic measurements showed this Ar-CF3 reductive elimination is largely insensitive to the electronic nature of the to-be-eliminated aryl substituent. Furthermore, the aryl group serves as the nucleophilic coupling partner in this reductive elimination process. The structure-reactivity relationship of biarylphosphine ligands was also investigated, uncovering distinct roles of the ipso-arene and alkoxy interactions in affecting these reductive elimination reactions. Part II. Copper-Catalyzed Carbon-Carbon and Carbon-Nitrogen Bond Formation via Olefin Functionalization Chapter 5. Copper-Catalyzed ortho C-H Cyanation of Vinylarenes A copper-catalyzed regioselective ortho C-H cyanation of vinylarenes has been developed. This method provides an effective means for the selective functionalization of vinylarene derivatives. A copper-catalyzed cyanative dearomatization mechanism is proposed to account for the regiochemical course of this reaction. This mechanism has been validated through density functional theory calculations. Computational studies revealed that the high level of ortho selectivity in the electrophilic cyanation event originates from a unique six-membered transition state that minimizes unfavorable steric repulsions. Chapter 6. Regio- and Stereospecific 1,3-Allyl Group Transfer Triggered by a Copper-Catalyzed Borylation/ortho-Cyanation Cascade A copper-catalyzed borylation/cyanation/allyl group transfer cascade has been developed. This process features an unconventional copper-catalyzed electrophilic dearomatization followed by the subsequent regio- and stereospecific 1,3-transposition of the allyl fragment enabled by the aromatization-driven Cope rearrangement. This method provides an effective means for the construction of adjacent tertiary and quaternary stereocenters with high levels of stereochemical purity. Chapter 7. Copper-Catalyzed Asymmetric Hydroamination of Unactivated Internal Olefins: an Effective Means to Access Highly Enantioenriched Aliphatic Amines Catalytic assembly of enantiopure aliphatic amines from abundant and readily available precursors has long been recognized as a paramount challenge in synthetic chemistry. We describe a mild and general copper-catalyzed hydroamination that effectively converts unactivated internal olefins-an important yet unexploited class of abundant feedstock chemicals-into highly enantioenriched [alpha]-branched amines (>/= 96% ee) featuring two minimally differentiated aliphatic substituents. This method provides a powerful means to access a broad range of advanced, highly functionalized enantioenriched amines of interest in pharmaceutical research and other areas.

Download or read book Cleavage of Carbon Carbon Single Bonds by Transition Metals written by Masahiro Murakami and published by John Wiley & Sons. This book was released on 2015-09-21 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by leading experts and pioneers in the field, this is the first up-to-date book on this hot topic. The authors provide synthetic chemists with different methods to activate carbon-carbon sigma bonds in organic molecules promoted by transition metal complexes. They explain the basic principles and strategies for carbon-carbon bond cleavage and highlight recently developed synthetic protocols based on this methodology. In so doing, they cover cleavage of C-C bonds in strained molecules, reactions involving elimination of carbon dioxide and ketones, reactions via retroallylation, and cleavage of C-C bonds of ketones and nitriles. The result is an excellent information source for researchers in academia and industry working in the field of synthetic organic chemistry, while equally serving as supplementary reading for advanced courses in organometallic chemistry and catalysis.

Download or read book Transition Metal catalyzed Cross coupling Methodologies for Carbon carbon Bond and Carbon nitrogen Bond Formation written by Ying Yu and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heterocycles from Transition Metal Catalysis written by András Kotschy and published by Springer Science & Business Media. This book was released on 2005-09-30 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Heterocycles from Transition Metal Catalysis: Formation and Functionalization" provides a concise summary of the prominent role of late transition metal (palladium, nickel, copper) catalysed processes in the synthesis and functionalization of heterocyclic systems. It gives an introduction to catalytic transformations, an overview of the most important reaction types, and presents synthetically useful catalytic processes classified by the target system and the type of transformation. The book provides a representative selection of transition metal catalysed reactions transformations that are relevant in heterocyclic chemistry. In this way, the authors present a useful resource for members of the academic community looking for a textbook as well as industrial chemists in search of a reference book. This book will be an invaluable resource for synthetic chemists, medicinal chemists, and those more generally interested in applied catalysis.

Download or read book Synthetic and Mechanistic Studies of Transition Metal Mediated Carbon Nitrogen Bond Forming Reactions written by Alexandra Eve Strom and published by . This book was released on 2015 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: The following dissertation discusses reactions for the formation of carbon-nitrogen bonds mediated by organotransition metal reagents and catalysts. Chapter 1 presents a synthetic method for the formal hydroamination of unactivated alkenes to form anti-Markovnikov primary and secondary amine products. This transformation is accomplished through the hydrozirconation and subsequent amination of alkenes. The method is then applied to the reaction of complex molecules to emphasize the functional group tolerance of these reactions. Chapter 2 of this thesis comprises the synthesis and evaluation of a series of rhodium-phosphine hydroamination catalysts. These complexes are evaluated in a series of catalytic intramolecular Markovnikov hydroamination reactions. The mechanism of hydroamination catalyzed by the rhodium(I) complexes in this study was examined computationally, and the turnover-limiting step was elucidated. The difference in reactivity of electron-rich and electron-poor catalysts was compared to the computational results of a computational ligand screen, and it was found that the computational analysis of reaction intermediates overestimated the reactivity of electron-poor catalysts. The analysis of the catalysts in this study was expanded to include the binding preference of each ligand, compared to the unsubstituted ligand, which corrects for the disparity between observed reactivity and the calculated overall reaction barrier for electron-poor ligands. The ligand-binding preferences for new ligand structures were calculated, and it was found that ligands that were predicted to bind strongly to rhodium had improved reactivity in catalytic reactions. Chapter 3 discusses the mechanistic study of the palladium-catalyzed aminocarbonylation of aryl halides with ammonia and CO to form primary benzamides. Conditions for reactions of aryl bromides, chlorides, and iodides are described, and the mechanism of reactions of aryl bromides was studied. The kinetic order in the concentration of aryl bromide was found to be first order, and the order in the pressure of CO was found to be inverse first order. These studies were complemented by DFT calculations on the mechanism of oxidative addition of aryl bromides. The products of oxidative addition, aroyl bromide palladium intermediates, were reacted with ammonia in the presence of additives to gain insight into the mechanism of release of product. The overall dependence on the rate of the catalytic reaction was found to be insensitive to excess ammonia, indicating that the overall turnover-limiting step of the reaction is during the oxidative addition step.

Download or read book Transition Metal Catalyzed Carbonylation Reactions written by Matthias Beller and published by Springer Science & Business Media. This book was released on 2013-08-13 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transition Metal Catalyzed Carbonylation Reactions is a comprehensive monograph focusing on carbon monoxide usage. This book provides students and researchers in organic synthesis with a detailed discussion of carbonylation from the basics through to applications. The authors have structured the book around the types of reactions, based on the different nucleophiles involved. Scientists working in carbonylation or with carbon monoxide, as well as teachers of organic synthesis can use this book to become familiar with this important area of organic chemistry.

Download or read book Development of New Transition Metal catalyzed Carbon fluorine Carbon nitrogen and Carbon carbon Bond Forming Processes written by Yuxuan Ye (Ph. D.) and published by . This book was released on 2018 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1. Palladium-Catalyzed Fluorination of Cyclic Vinyl Triflates: Dramatic Effect of TESCF3 as an Additive A method for the synthesis of cyclic vinyl fluorides with high levels of regiochemical fidelity has been achieved by Pd-catalysis employing a new biarylphosphine ligand and TESCF3 as a crucial additive. Five, six, and seven-membered vinyl triflate substrates, as well as a few acyclic substrates undergo the transformation successfully. The intriguing "TESCF3 effect" provided a new tool for addressing the problem of the formation of regioisomers in Pd-catalyzed fluorination reactions. Chapter 2. Mechanistic Studies on Pd-Catalyzed Fluorination of Cyclic Vinyl Triflates: Evidence for in situ Ligand Modification by TESC3 as an additive. A detailed mechanistic hypothesis for the Pd-catalyzed fluorination of cyclic vinyl triflates, and the unusual effect of TESCF3 as an additive has been developed by combined experimental and computational studies. The preference of conducting [beta]-hydrogen elimination rather than reductive elimination from the trans-LPd(vinyl)F complex, which is generated predominantly due to the trans-effect, caused the poor regioselectivity of the fluorination reaction under TESCF3-free conditions. An in situ ligand modification by trifluoromethyl anion, leading to the generation of the cis-LPd(vinyl)F complex which prefers reductive elimination rather than Phydrogen elimination, is proposed to be responsible for the improved regioselectivity of the fluorination reaction when TESCF3 was used as an additive. Chapter 3. CuH-Catalyzed Enantioselective Alkylation of Indoles with Ligand-Controlled Regiodivergence A method for the enantioselective synthesis of either NI- and C3-chiral indoles by CuH-catalysis, depending on the choice of ligand, was developed. In contrast to conventional indole functionalization in which indoles are used as nucleophiles, hydroxyindole derivatives are employed as electrophiles in this method. DFT calculations indicated that the extent to which the Cu-P bonds of the alkylcopper intermediate distort, determines the regioselectivity of the reaction.

Download or read book Mechanistic Studies on Metal catalyzed Carbon nitrogen Bond Forming Reactions written by Eric R. Strieter and published by . This book was released on 2005 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) A systematic mechanistic analysis of Pd(OAc)2/ monophosphino- biaryl-catalyzed C-N bond forming reactions with aryl chlorides has been performed. The results provide insights into the relationship between the steady-state concentration of active Pd and the size and substitution pattern of the monophosphinobiaryl ligands. These insights into the nature of catalyst activation help highlight the importance of establishing a high concentration of active catalyst. The catalyst derived from the bulkiest ligand in the series, the tri-i-propyl ligand 13, exhibits both accelerated rate and the increased stability required for practical application of this reaction.

Download or read book Asymmetric Catalysis from a Chinese Perspective written by Shengming Ma and published by Springer Science & Business Media. This book was released on 2011-07-06 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Qi-Lin Zhou and Jian-Hua Xie: Chiral Spiro Catalysts.- Fuk Loi Lam, Fuk Yee Kwong and Albert S. C. Chan: Chiral Phosphorus Ligands with Interesting Properties and Practical Applications.- Jiang Pan, Hui-Lei Yu, Jian-He Xu, Guo-Qiang Lin: Advances in Biocatalysis: Enzymatic Reactions and Their Applications.- Mei-Xiang Wang: Enantioselective Biotransformations of Nitriles.- Man Kin Wong, Yiu Chung Yip and Dan Yang: Asymmetric Epoxidation Catalyzed by Chiral Ketones.- W. J. Liu, N. Li and L. Z. Gong: Asymmetric Organocatalysis.- Qing-Hua Fan and Kuiling Ding: Enantioselective Catalysis with Structurally Tunable Immobilized Catalysts.- Chang-Hua Ding, Xue-Long Hou: Transition Metal-Catalyzed Asymmetric Allylation.- Jian Zhou and Yong Tang: Enantioselective Reactions with Trisoxazolines.- Xiang-Ping Hu, Duo-Sheng Wang, Chang-Bin Yu, Yong-Gui Zhou, and Zhuo Zheng: Adventure in Asymmetric Hydrogenation: Synthesis of Chiral Phosphorus Ligands and Asymmetric Hydrogenation of Heteroaromtics.

Download or read book Advances in Late Metal Carbon Nitrogen Bond Formation for the Synthesis of Substituted Heterocycles written by Nicolas Rotta-Loria and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Late-metal catalyzed cross-couplings have emerged as efficient and selective methodologies for the formation of C-C and C-N bonds. The ability to synthesize complex heterocycles from cheap and abundant starting materials is an invaluable asset to the pharmaceutical industry, given that many pharmaceuticals contain at least one heterocyclic component. This reactivity can be achieved by tuning the steric and electronic properties of ancillary ligands to support metal catalysts in the reaction steps leading to the target substrate. The Stradiotto group has developed several state-of-the-art methodologies involving ligands for palladium catalysis, for both C-C and C-N bond-forming reactions. These methodologies can be amalgamated into a multicomponent reaction platform to synthesize more complex products from simple materials. Chapter 1 outlines this concept with the application of a Mor-DalPhos/Pd catalyst in the one-pot synthesis of indoles from acetone and simple amines involving C-C and C-N bond formation. The robust nature of this method can be extended to include benchtop reaction conditions in a one-step, one-pot synthesis of indoles, thus representing a useful synthetic protocol. While palladium provides a powerful tool for C-C and C-N bond formation, the general trend in catalysis has shifted away from the precious metals toward first row metals as economic alternatives. Nickel complexes have recently emerged as excellent catalysts for a number of amination reactions. The ability to utilize ammonia also represents a sought after reaction, due to the widespread availability and synthetic utility of amino-functionalized products. In this regard, Chapter 2 will focus on the development and application of both commercially available and strategically designed ligand classes for the monoarylation of ammonia with substituted heterocycles. Hydrazine represents an important synthon in synthetic chemistry. It is synthesized on multi-ton scale every year and represents an important building block in many industrial processes. Many synthetic challenges arise from using free hydrazine as reactant, which has led to lethargic growth of its application in the field of late-metal catalyzed C-N bond-formation. However, gold-catalyzed methodologies have been developed utilizing NHC ligands to allow for the hydrohydrazination of alkynes with parent hydrazine. Chapter 4 examines the development and application of a series of (PR3)AuCl complexes for use in such transformations, leading to the identification of the first effective phosphine-bound gold complex for use in the hydrohydrazination of alkynes at room temperature.

Download or read book Transition Metal Catalyzed Carbene Transformations written by Jianbo Wang and published by John Wiley & Sons. This book was released on 2022-05-16 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents an up-to-date overview of the rapidly growing field of carbene transformations Carbene transformations have had an enormous impact on catalysis and organometallic chemistry. With the growth of transition metal-catalyzed carbene transformations in recent decades, carbene transformations are today an important compound class in organic synthesis as well as in the pharmaceutical and agrochemical industries. Edited by leading experts in the field, Transition Metal-Catalyzed Carbene Transformations is a thorough summary of the most recent advances in the rapidly expanding research area. This authoritative volume covers different reaction types such as ring forming reactions and rearrangement reactions, details their conditions and properties, and provides readers with accurate information on a wide range of carbene reactions. Twelve in-depth chapters address topics including carbene C-H bond insertion in alkane functionalization, the application of engineered enzymes in asymmetric carbene transfer, progress in transition-metal-catalyzed cross-coupling using carbene precursors, and more. Throughout the text, the authors highlight novel catalytic systems, transformations, and applications of transition-metal-catalyzed carbene transfer. Highlights the dynamic nature of the field of transition-metal-catalyzed carbene transformations Summarizes the catalytic radical approach for selective carbene cyclopropanation, high enantioselectivity in X-H insertions, and bio-inspired carbene transformations Introduces chiral N,N'-dioxide and chiral guanidine-based catalysts and different transformations with gold catalysis Discusses approaches in cycloaddition reactions with metal carbenes and polymerization with carbene transformations Outlines multicomponent reactions through gem-difunctionalization and transition-metal-catalyzed cross-coupling using carbene precursors Transition Metal-Catalyzed Carbene Transformations is essential reading for all chemists involved in organometallics, including organic and inorganic chemists, catalytic chemists, and chemists working in industry.

Download or read book Metal Catalyzed Reductive C C Bond Formation written by Michael J Krische and published by Springer Science & Business Media. This book was released on 2007-10-05 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by numerous experts

Download or read book New Carbon Carbon Coupling Reactions Based on Decarboxylation and Iron Catalyzed C H Activation written by Rui Shang and published by Springer. This book was released on 2016-12-09 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the latest developments in new catalytic C–C bond formation methods using easily accessible carboxylate salts through catalytic decarboxylation with good atom economy, and employing the sustainable element iron as the catalyst to directly activate C–H bonds with high step efficiency. In this regard, it explores a mechanistic understanding of the newly discovered decarboxylative couplings and the catalytic reactivity of the iron catalyst with the help of density functional theory calculation. The thesis is divided into two parts, the first of which focuses on the development of a series of previously unexplored, inexpensive carboxylate salts as useful building blocks for the formation of various C–C bonds to access valuable chemicals. In turn, the second part is devoted to several new C–C bond formation methodologies using the most ubiquitous transition metal, iron, as a catalyst, and using the ubiquitous C–H bond as the coupling partner.

Download or read book Regioselective Carbon nitrogen Bond Formation Via Oxidative Transition Metal Catalysis written by Louis Marchetti and published by . This book was released on 2015 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earth Abundant Transition Metal Catalyzed Reactions written by and published by Elsevier. This book was released on 2024-09-18 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earth-Abundant Transition Metal Catalyzed Reactions, Volume 74 in the Advances in Catalysis series, highlights new advances in the field, with this new volume presenting interesting chapters. Each chapter is written by an international board of authors. Chapters in this new release include in Chiral Iron Complexes for Asymmetric Catalysis, Recent advances in Ni-catalyzed Functionalization of Strong C-O and C-H Bonds, Low-valent Molecular Cobalt Complexes for Reductive Chemistry, Iron-catalyzed group-transfer reactions with hypervalent iodine reagents, and Iron Porphyrins for Mediating Atom Efficient C–C Bond Formations. Provides the authority and expertise of leading contributors from an international board of authors Presents the latest release in Advances in Catalysis serials Updated release includes the latest information in the field