Download or read book Heteroaryl Carbene Complexes written by Belinda Van der Westhuizen and published by . This book was released on 2013 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organometallic Reagents in Organic Synthesis written by John H. Bateson and published by . This book was released on 1994 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text reviews the use of organometallic reagents in organic synthesis. In particular, it covers their roles in activating small molecules, such as oxygen and hydrogen, into larger structures, and their ability to confer diastereo- and enantio-selectivity.
Download or read book Functionalised N Heterocyclic Carbene Complexes written by Olaf Kühl and published by John Wiley & Sons. This book was released on 2010-02-02 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Transition Metals in the Synthesis of Complex Organic Molecules written by Louis S. Hegedus and published by University Science Books. This book was released on 1999 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition offers easy access to the field of organotransition metal chemistry. The book covers the basics of transition metal chemistry, giving a practical introduction to organotransition reaction mechanisms.
Download or read book The Organometallic Chemistry of N heterocyclic Carbenes written by Han Vinh Huynh and published by John Wiley & Sons. This book was released on 2017-02-03 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Organometallic Chemistry of N-heterocyclic Carbenes describes various aspects of N-heterocyclic Carbenes (NHCs) and their transition metal complexes at an entry level suitable for advanced undergraduate students and above. The book starts with a historical overview on the quest for carbenes and their complexes. Subsequently, unique properties, reactivities and nomenclature of the four classical NHCs derived from imidazoline, imidazole, benzimidazole and 1,2,4-triazole are elaborated. General and historically relevant synthetic aspects for NHCs, their precursors and complexes are then explained. The book continues with coverage on the preparation and characteristics of selected NHC complexes containing the most common metals in this area, i.e. Ni, Pd, Pt, Ag, Cu, Au, Ru, Rh and Ir. The book concludes with an overview and outlook on the development of various non-classical NHCs beyond the four classical types. Topics covered include: Stabilization, dimerization and decomposition of NHCs Stereoelectronic properties of NHCs and their evaluation Diversity of NHCs Isomers of NHC complexes and their identification NMR spectroscopic signatures of NHC complexes normal, abnormal and mesoionic NHCs The Organometallic Chemistry of N-heterocyclic Carbenes is an essential resource for all students and researchers interested in this increasingly important and popular field of research.
Download or read book Metal Carbenes in Organic Synthesis written by Florencio Zaragoza Dörwald and published by John Wiley & Sons. This book was released on 2008-09-26 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are hardly more versatile compounds in organic synthesis than carbene complexes. The rapid development of new synthetic methods involving carbene complexes - stereoselective cyclopropanation, carbonyl olefination, olefin metathesis, etc. - reveals the value and high potential of these compounds. Their application ranges from the synthesis of fine chemicals to polymer production. This comprehensive, well structured handbook presents the fundamental principles and the recent advances in carbene complex chemistry. Arranged according to structure and reactivity, all relevant classes of carbene complexes, their generation, and application in organic synthesis are discussed in detail. Critically selected, up-to-date references and valuable experimental procedures await the reader. Every chemist searching for a concise introduction and reference work for carbene complex chemistry will welcome this practical guide. "...this concise presentation of all the aspects of the use of carbene complexes in synthesis will help provide the impetus for even more rapid developments in this field of research." R. H. Grubbs (Caltech)
Download or read book Fischer and N heterocyclic Carbene Complexes of Tungsten 0 written by René Pretorius and published by . This book was released on 2012 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The synthesis of novel Fischer and N-heterocyclic tungsten(0) carbene complexes was endeavoured in this study and resulted in the synthesis, isolation and characterisation of eighteen new complexes. Sixteen novel Fischer carbene complexes were synthesised. In these complexes, both carbene ligand substituents were varied. Ethoxy as well as amino heteroatom substituents were used. Heteroaryl compounds thiophene and furan were employed as the second substituents on the carbene ligand. Complexes with combinations of these different substituents were synthesised and investigated to assess the influence the various substituents of the carbene ligand may have on the carbene complex itself. In addition, the metal ligand sphere was altered by substitution of one or two carbonyl ligands for either an amine or a phosphine ligand/s. These substitutions resulted in the formation of metal pentacarbonyl, metal tetracarbonyl as well as metal tricarbonyl systems. The complexes were successfully characterised by means of NMR and IR spectroscopy, and in selected cases X-ray diffraction and mass spectrometry. Synthesis of N-heterocyclic carbene complexes derived from isopropyl and mesityl imidazolium chlorides was attempted. The products were obtained in crude form, but could not be isolated due to decomposition during purification. Two novel decomposition products, which point towards a unique decomposition route, were isolated. Theoretical models of both the novel Fischer carbene complexes and the N-heterocyclic carbene complexes were calculated. This allowed for identification of infrared modes observed in experimental data. Furthermore, the HOMO and LUMO distributions and the HOMO-LUMO energy gaps were calculated, along with electrostatic potential maps. In all the Fischer carbene complexes the HOMOs were located on the metal centre and the LUMOs on the carbene ligand. In contrast, the HOMO and the LUMO were both located on the metal centre for the N-heterocyclic carbenes. The HOMO-LUMO energy gap decreased as follows: NHC complexes > Amino Fischer carbene complexes > Ethoxy Fischer carbene complexes Lastly, in all the complexes studied, the electrostatic potential maps indicated that the highest amount of electron density was found on the carbonyl ligands of these complexes. Both experimental and theoretical data indicated marked differences in the various classes of compounds, suggesting that these complexes would not only have different reactivities but also be suited to different applications. Experimental studies on reactivity and applications are thus future avenues of study which are made available from these results.
Download or read book Click Triazoles written by Janez Košmrlj and published by Springer. This book was released on 2012-05-30 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: B. R. Buckley and H. Heaney: Mechanistic Investigations of Copper(I)- Catalyzed Alkyne–Azide Cycloaddition Reactions.- J. D. Crowley and D. A. McMorran: “Click-Triazole” Coordination Chemistry: Exploiting 1,4-Disubstituted-1,2,3-Triazoles as Ligands.- S. Lee and A. H. Flood: Binding Anions in Rigid and Reconfigurable Triazole Receptors.- M. Watkinson: Click Triazoles as Chemosensors.- H.-F. Chow, C.-M. Lo and Y. Chen: Triazole-Based Polymer Gels.- T. Zheng, S. H. Rouhanifard, A. S. Jalloh, P. Wu: Click Triazoles for Bioconjugation.- S. Mignani, Y. Zhou, T. Lecourt and L. Micouin: Recent Developments in the Synthesis 1,4,5-Trisubstituted Triazoles.
Download or read book Iron Carbene Complexes written by Wolfgang Petz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: E.O. Fischer received the Nobel prize in 1973 for the investigations of complexes with a formal metal atom-carbon double bond. Among these, the Iron-Carbene species is readily available and has proved to be a versatile reagent in organic syntheses. It is rather simple to tune the electronicproperties of this Fischer Carbene and to control reactivity and stereospecificity of the reagent in, e.g., cyclopropanation reactions. This first volume of the "Scripts in Inorganic and Organome- tallic Chemistry" addresses graduate students in the fields ofcoordination compounds and organic synthesis. It covers the chemistry and structural aspects of iron-carbon com- pounds with a iron-carbon double bond. The first part deals with the carbene moiety, the second with vinylidene ligands.
Download or read book Synthesis of Bifunctional Pincer Metal Complexes Containing N heterocyclic Carbenes written by Derek B. Brown and published by . This book was released on 2010 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research is to synthesize pincer ligands and complexes with a central pyridine ligand substituted at positions 2 and 6 by two N-heterocyclic carbenes, each bearing a pendant heteroaryl substituent. Related pincers without heteroaryl groups have been reported in the past 15 years as catalysts, and our ultimate goal was to enable the study of the heteroaryl moieties as pendant bases, creating improved bifunctional catalysts. Two classes of pincers were made: one with methylene spacers between the central pyridine and the imidazol-2-ylidene groups, and those whose imidazol-2-ylidene groups were attached directly to the pyridine without any spacers. Four bis(imidazolium) salt pincer precursors with methylene spacers were made, and reaction with Ag2O produced silver-carbene complexes which act as transmetallation agents for further complexation. Two of the analogs were able to be metallated with (COD)PdCl2 to form palladium-carbene complexes, NMR data for which are in accord with a puckered structure induced by the methylene spacers. One of these complexes showed catalytic activity in the Heck coupling reaction. Synthesis of analogs lacking spacers under literature conditions proved to be impossible, presumably because of reduced nucleophilicity of 1-heteroarylimidazoles. Thus, a systematic study of reactivity of 1-substituted imidazoles with five 2,6-disubstituted pyridines conclusively showed that 2,6-bis(trifluoromethanesulfonyloxy)pyridine (16) was the best precursor. A well-described synthesis of 16 was developed, paving the way to making seven analogs of pincer precursors without methylene spacers. Reaction of two of these pincer precursors with Ag2O and NaOH produced silver-carbene bridged-dimer complexes which were characterized by X-ray diffraction and show promise as sources of other metal complexes.
Download or read book Transition Metal Catalyzed Carbene Transformations written by Jianbo Wang and published by John Wiley & Sons. This book was released on 2021-12-20 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 N Heterocyclic Carbenes in Organocatalysis written by Akkattu T. Biju and published by John Wiley & Sons. This book was released on 2019-01-07 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarizing the emerging field of N-heterocyclic carbenes used in organocatalysis, this is an excellent overview of the synthesis and applications of NHCs focusing on carbon-carbon and carbon-heteroatom bond formation. Alongside comprehensive coverage of the synthesis, characteristics and applications, this handbook and ready reference also includes chapters on NHCs for polymerization reactions and natural product synthesis.
Download or read book N Heterocyclic Carbenes written by Silvia Diez-Gonzalez and published by Royal Society of Chemistry. This book was released on 2010-11-26 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last fifteen years, N-heterocyclic carbenes (NHCs) have mostly been used as ancillary ligands for the preparation of transition metal-based catalysts. Compared to phosphorus-containing ligands, NHCs tend to bind more strongly to metal centres, avoiding the necessity for the use of excess ligand in catalytic reactions. The corresponding complexes are often less sensitive to air and moisture, and have proven remarkably resistant to oxidation. Recent developments in catalysis applications have been facilitated by the availability of carbenes stable enough to be bottled, particularly for their use as organocatalysts. This book shows how N-heterocyclic carbenes can be useful in various fields of chemistry and not merely laboratory curiosities or simple phosphine mimics. NHCs are best known for their contribution to ruthenium and palladium-catalysed reactions but the scope of this book is much broader. The synthesis of NHC ligands and their corresponding metal complexes are covered in depth. Moreover, the biological activity of NHC-containing complexes, as well as an overview of their theoretical aspects are included. Such metal species are further examined, not only in terms of their catalytic applications, but also of their stereoelectronic parameters and reactivity/stability. Finally, special attention is given to the hot topic of organocatalysis. The book will be of interest to postgraduates, academic researchers and those working in industry.
Download or read book Carbene Chemistry written by Wolfgang Kirmse and published by Elsevier. This book was released on 2012-12-02 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic Chemistry, Volume 1: Carbene Chemistry is a 12-chapter text that covers pertinent research studies on the carbene chemistry. The first ten chapters are devoted to comprehensive surveys of carbene chemistry. Each chapter tackles specific carbene compound, such as olefinic and acetylenic carbenes, aryl and diarylcarbenes, carboalkoxycarbenes, ketocarbenes, halocarbenes, heteroatom-containing carbenes, and dicarbenes. The formation, synthesis, and reactions of these compounds are discussed. The remaining two chapters the excess energy in reactions and spin states of carbenes. This book will be of value to organic chemists, organic chemistry researchers, teachers, and students.
Download or read book N Heterocyclic Carbenes written by Steven P. Nolan and published by John Wiley & Sons. This book was released on 2014-07-07 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: This comprehensive reference and handbook covers in depth all major aspects of the use of N-heterocyclic carbene-complexes in organic synthesis: from the theoretical background to characterization, and from cross-coupling reactions to olefin metathesis. Edited by a leader and experienced scientist in the field of homogeneous catalysis and use of NHCs, this is an essential tool for every academic and industrial synthetic chemist.
Download or read book Platinum Carbene Complexes with One Heteroatom Bonded to Carbene Carbon Synthesis and Mechanisms written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Organic Functional Group Transformations Synthesis carbon with one heteroatom attached by a multiple bond written by Alan R. Katritzky and published by Elsevier. This book was released on 1995 with total page 968 pages. Available in PDF, EPUB and Kindle. Book excerpt:
