Download or read book Iridium Catalyzed Aromatic Borylation and Its Applications in One pot Preparations of Substituted Aromatic Building Blocks written by Ghayoor Abbas Chotana and published by . This book was released on 2009 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthetic Applications of Iridium catalyzed Aromatic C H Borylation written by Feng Shi and published by . This book was released on 2007 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Developing and Understanding Iridium catalysed Arene Borylation written by Peter Harrisson and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Iridium catalysed C-H borylation has moved from an interesting observation to an efficient catalytic reaction. This work has developed and improved upon some of the key issues associated with the methodology. The one-pot conversion of aryl boronates, generated by C-H borylation, to other functionality has been one area of interest. However, reactions typically require a change in reaction solvent to make this possible. This thesis describes a one-pot, single solvent C-H borylation/Suzuki-Miyaura cross-coupling sequence. The key to this transformation is the use of methyl tert-butyl ether (MTBE). This procedure allows efficient synthesis of biaryls by initial C-H borylation of aromatic substrates followed by addition of water, subsequent reagents and aryl halide to complete the Suzuki-Miyaura cross-coupling without the need for change in reaction solvent. Another issue associated with the C-H borylation reaction is the extended reaction times required for some substrates. This issue was tackled by development of a microwave accelerated C-H borylation reaction. Microwave reactions are conducted at the same temperature as standard heated reactions with accelerations of 2 - 24 times affording comparable product yields. Typically reaction times were reduced from hours to minutes. A microwave accelerated one-pot, single solvent C-H borylation/Suzuki-Miyaura cross-coupling sequence allowed synthesis of biaryls from arene plus aryl halides in reaction times of minutes. Subsequent work focussed on the borylation of novel substrates classes, in particular quinolines. The borylation of substituted quinolines highlighted interesting electronic selectivity of the reaction. The site of borylation can be directed by changing the nature of the substituent on the ring. DFT calculations have been conducted to gain understanding into the causes of selectivity. A link between C-H acidity, calculated by DFT methods, and the borylation site was observed. Preliminary studies into the borylation of azaindoles are discussed. Studies towards a procedure to convert aryl boronates to trifluoromethyl groups are also been introduced.

Download or read book Iridium Catalyzed C H Activation borylation of Aromatic heteroaromatic Substrates and Its Application in Small Molecule Synthesis written by Venkata Apparao Kallepalli and published by . This book was released on 2010 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Iridium catalyzed Borylation of Aromatic and Aliphatic C H Bonds Methodology and Mechanism written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Iridium Catalysis written by Pher G. Andersson and published by Springer Science & Business Media. This book was released on 2011-01-05 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the contents: Robert H Crabtree: Introduction and History. - Montserrat Diéguez, Oscar Pàmies and Carmen Claver: Iridium-catalysed hydrogenation using phosphorous ligands. - David H. Woodmansee and Andreas Pfaltz: Iridium Catalyzed Asymmetric Hydrogenation of Olefins with Chiral N,P and C,N Ligands. - Ourida Saidi and Jonathan M J Williams: Iridium-catalyzed Hydrogen Transfer Reactions. - John F. Bower and Michael J. Krische: Formation of C-C Bonds via Iridium Catalyzed Hydrogenation and Transfer Hydrogenation. - Jongwook Choi, Alan S. Goldman: Ir-Catalyzed Functionalization of CH Bonds. - Mark P. Pouy and John F. Hartwig: Iridium-Catalyzed Allylic Substitution. - Daniel Carmona and Luis A. Oro: Iridium-catalyzed 1.3-dipolar cycloadditions.

Download or read book Computational Studies of Iridium catalyzed Borylation Reactions and Defying Torquoselectivity in Cyclobutene Ring opening Via Strain induced Thermal Selectivity written by Aaron Gabriel Green and published by . This book was released on 2013 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: The studies reported in this dissertation illustrate a few selected examples of using density functional theory (DFT) calculations to investigate various aspects of iridium-catalyzed reactions and ring-opening of bicyclic cyclobutene rings. These computational predictions not only reproduce and explain experimental results and offer insights to reaction mechanisms, but also provide theoretical models to predict reactivity, regio- and stereoselectivities. Chapter 1 is a review surveying the literature of iridium-catalyzed borylation reactions. Emphasis is placed on iridium-catalyzed borylation of alkenes and arenes. In particular, I discuss the history leading up to the current catalyst systems for iridium-catalyzed borylation reactions, and regioselectivity of borylation for a number of different substrates. Despite the large amount of work on iridium-catalyzed borylation reactions, this review shows that there is still much to be understood regarding the origins of observed regioselectivities. Chapters 2 and 3 describe theoretical investigations of Ir(III)-catalyzed borylation reactions. The origins of regioselectivities observed in the borylation of pyridine are discussed in Chapter 2. The high selectivity for borylation at the 3- and 4- position of pyridine is attributed to the formation of a Lewis acid-base complex between pyridine and either boron species or iridium species in solution. The origins of regioselectivities for the iridium-catalyzed borylation of substituted arenes and 5-membered heterocycles are discussed in Chapter 3. The distortion/interaction model was employed to understand the origins of the selectivities in these reactions. Computations revealed that regioselectivity is mainly controlled by differences in the interaction energies between the iridium catalyst and arene carbon. Chapter 4 illustrates a theoretical study of ring-opening in strained, trans-substituted cyclobutenes. The torquoselectively preferred outward ring-opening products are unable to form due to ring strain inherent in 9- and 10-membered macrocyclic (E, E)-1,3-dienes. As a result of this study, I propose a general methodology for stereoselective synthesis of macrocyclic (Z, Z)-1,3-dienes termed strain-induced thermal selectivity (SITS).

Download or read book Arene Chemistry written by Jacques Mortier and published by John Wiley & Sons. This book was released on 2015-11-30 with total page 992 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organized to enable students and synthetic chemists to understand and expand on aromatic reactions covered in foundation courses, the book offers a thorough and accessible mechanistic explanation of aromatic reactions involving arene compounds. • Surveys methods used for preparing arene compounds and their transformations • Connects reactivity and methodology with mechanism • Helps readers apply aromatic reactions in a practical context by designing syntheses • Provides essential information about techniques used to determine reaction mechanisms

Download or read book Journal written by American Chemical Society and published by . This book was released on 2003 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Allied Studies on Total Sythesis of Cyclic Tripeptide Tmc 95 Via an Iridium Catalyzed Borylation deborylation Strategy and Teaching Organic Chemistry in words written by Fangyi Shen and published by . This book was released on 2019 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arylboronate esters are versatile synthetic building blocks. Iridium catalyzed C-H activation/borylation reactions are a green way of making such building blocks as these reactions often obviate the need for prior functionalization (e.g. halogenation), the use of pyrophoric reagents, cryogenic conditions, etc. Installation of multiple boron substituents about the starting arene and then Ir catalyzed selective deborylation of the individual borons can allow for the formation of an even greater diversity of borylated building blocks.The regioselectivity of Ir-catalyzed borylation is usually driven by sterics, however heterocycles are known to borylated at positions that exhibit heightened C-H acidity through the influence of the heteroatom. The regioselective borylation attained with a tryptophan derivative has been utilized in the development of a novel convergent route to the TMC-95 core. While pursuing a model synthesis of this natural product, the ability of bismuth salts to catalyze deborylations was discovered. These bismuth salts mediated methods can be highly selective in the in the deborylation of di and triborylated indoles. Furthermore, bismuths compounds are safe and less expensive as compared to the Ir-catalysts that facilitated deborylation. Numerous screening experiments on both substrates and other metal salts afforded a better understanding of how these novel deborylations can be applied in various synthetic settings and provided insight into possible mechanisms.Also, while I was a teaching assistant and a fixed-term instructor during my graduate studies at Michigan State University, I gradually realized that teaching is my passion and I am prepared to start my independent career and be an independent thinking teacher for the organic chemistry area.Owing to the nature of the subject, organic chemistry can be very visually distracting, and the image can be overpowering during student's learning. Like it or not students will try memorization first, our hypothesis is that once they know the "organic transformation formula" in words, via memorization or any other method, then introducing them to the structures of these functional groups will come with added context, and once they make that jump from word to structure they will be in a better position to understand reaction mechanisms. More importantly, understanding those reaction mechanisms will enable the student to progress to more complex topics.By introducing functional group transformations without the "clutter" of structures, we predict that once structures are introduced students will prioritize what's important because they will have trained their minds to ask what is the functional group, not "where did I see that structure in my notes".In short, we aim to train students to focus their attention on the reactive functional group of an organic molecule by emphasizing the use of WORDS to describe functional group transformation and teach the organic chemistry as the second language.

Download or read book Frontiers in Iridium Catalyzed C H Borylation written by Matthew Alan Larsen and published by . This book was released on 2016 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: The following dissertation discusses the development of novel methodology for the catalytic borylation of C-H bonds and includes in-depth studies on the mechanism and selectivity of these synthetic transformations. These methods include the borylation of heteroaryl C-H bonds, the selective borylation of benzylic C-H bonds, and the directed and undirected borylation of unactivated alkyl C-H bonds. Chapter 1 contains a comprehensive review of C-H borylation methodology. This review focuses on the initial development of catalytic C-H borylation and on the state-of- the-art of methodology for the undirected and directed borylation of aryl, benzylic, and alkyl C-H bonds. Additionally, this review highlights knowledge gaps and unsolved challenges. Furthermore, this review provides the author's opinion on future directions for research on the borylation of C-H bonds. Chapter 2 describes the study of the iridium-catalyzed borylation of heteroaryl C- H bonds. Contained is an examination of the scope of the borylation of heterocycles containing more than one heteroatom and rules for predicting the site-selectivity of this reaction. Also included are experimental and computational studies that reveal the mechanism of this reaction and the origins of the observed regioselectivity. Chapter 3 discusses the development of the selective borylation of the primary benzylic C-H bonds of methylarenes. Key to this development was the discovery that the combination of a novel iridium catalyst and a silylborane allows for the selective borylation of benzylic C-H bonds over aryl C-H bonds. Experimental and computational studies that investigate the origins of this selectivity are also discussed. Chapter 4 discusses the development of the iridium-catalyzed, hydrosilyl-directed borylation of alkyl C-H bonds. This methodology allows for the diastereoselective borylation of secondary alkyl C-H bonds under relatively mild conditions. Chapter 5 explores the effect of ligand structure on the rates of alkyl C-H borylation catalyzed by Ir-phenanthroline complexes. Experimental and computational studies reveal that in addition to the relative electron-donating ability of phenanthrolines, weak interactions involving the phenanthroline in the transition state of the turnover- limiting step for the borylation of alkyl C-H bonds can have a large impact on the relative rates of alkyl C-H borylation catalyzed by various Ir-phenanthroline complexes.

Download or read book Pincer Compounds written by David Morales-Morales and published by Elsevier. This book was released on 2018-04-11 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pincer Compounds: Chemistry and Applications offers valuable state-of-the-art coverage highlighting highly active areas of research—from mechanistic work to synthesis and characterization. The book focuses on small molecule activation chemistry (particularly H2 and hydrogenation), earth abundant metals (such as Fe), actinides, carbene-pincers, chiral catalysis, and alternative solvent usage. The book covers the current state of the field, featuring chapters from renowned contributors, covering four continents and ranging from still-active pioneers to new names emerging as creative strong contributors to this fascinating and promising area. Over a decade since the publication of Morales-Morales and Jensen’s The Chemistry of Pincer Compounds (Elsevier 2007), research in this unique area has flourished, finding a plethora of applications in almost every single branch of chemistry—from their traditional application as very robust and active catalysts all the way to potential biological and pharmaceutical applications. Describes the chemistry and applications of this important class of organometallic and coordination compounds Includes contributions from global leaders in the field, featuring pioneers in the area as well as emerging experts conducting exciting research on pincer complexes Highlights areas of promising and active research, including small molecule activation, earth abundant metals, and actinide chemistry

Download or read book Boronic Acids written by Dennis G. Hall and published by John Wiley & Sons. This book was released on 2006-05-12 with total page 571 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the first time, the whole field of organoboronic acids is presented in one comprehensive handbook. Professor Dennis Hall, a rising star within the community, covers all aspects of this important substance class, including applications in chemistry, biology and medicine. Starting with an introduction to the structure, properties, and preparation of boronic acid derivatives, together with an overview of their reactions and applications, the book goes on to look at metal-catalyzed borylation of alkanes and arenas, coupling reactions and rhodium-catalyzed additions of boronic acids to alkenes and carbonyl compounds. There follows chapters on copper-promoted C-O and C-N cross-coupling of boronic acids, recent applications in organic synthesis, as well as alpha-haloalkylboronic esters in asymmetric synthesis. Later sections deal with cycloadditions, organoboronic acids, oxazaborolidines as asymmetric inducers, and boronic acid based receptors and sensors. The whole is rounded off with experimental procedures, making this invaluable reading for organic, catalytic and medicinal chemists, as well as those working in organometallics.

Download or read book Remote C H Bond Functionalizations written by Debabrata Maiti and published by John Wiley & Sons. This book was released on 2021-04-26 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: A guide to contemporary advancements in the field of distal C-H functionalizations An important and dynamic topic within the modern field of organic synthesis, selective functionalization of C-H bonds can be used in a variety of applications across the pharmaceutical and agrochemical industries. Remote C-H Bond Functionalizations presents an inclusive account of the most recent developments and potential applications of performing variegated functionalizations selectively at the distal positions of organic compounds. Featuring contributions by an international team of experts, this authoritative volume provides deep insight into distal functionalizations, including detailed discussion of mechanisms, the engineering of templates, and the design of strategies. The text covers a diverse range of topics including C-H functionalization of palladium/norbornene catalysis, ruthenium-catalyzed remote functionalization, the non-directed distal C(sp2)-H, functionalization, transition metal catalyzed distal para-selective C-H functionalization, and much more. Reviewing contemporary advancements in the field while laying the foundation for future research, this important resource: Provides the most recent research and thorough coverage of the subject available in a single volume Offers practical information on C-H functionalizations in various industries Includes an up-to-date introduction to distal C-H functionalizations Remote C-H Bond Functionalizations is a must-read for every synthetic chemist, including chemists working with organometallics, organic chemists and researchers, and industrial chemists.

Download or read book Olefin Polymerization written by Walter Kaminsky and published by Wiley-VCH. This book was released on 2006-08-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: With an enormous velocity, olefin polymerization has expanded to one of the most significant fields in polymers since the first industrial use about 50 years ago. In 2005, 100 million tons of polyolefins were produced - the biggest part was catalyzed by metallorganic compounds. The Hamburg Macromolecular Symposium 2005 with the title "Olefin Polymerization" involved topics such as new catalysts and cocatalysts, kinetics, mechanism and polymer reaction engineering, synthesis of special polymers, and characterization of polyolefins. The conference combined scientists from different disciplines to discuss latest research results of polymers and to offer each other the possibility of cooperation. This is reflected in this volume, which contains invited lectures and selected posters presented at the symposium.

Download or read book Mechanochemical Organic Synthesis written by Davor Margetic and published by Elsevier. This book was released on 2016-04-23 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanochemical Organic Synthesis is a comprehensive reference that not only synthesizes the current literature but also offers practical protocols that industrial and academic scientists can immediately put to use in their daily work. Increasing interest in green chemistry has led to the development of numerous environmentally-friendly methodologies for the synthesis of organic molecules of interest. Amongst the green methodologies drawing attention, mechanochemistry is emerging as a promising method to circumvent the use of toxic solvents and reagents as well as to increase energy efficiency. The development of synthetic strategies that require less, or the minimal, amount of energy to carry out a specific reaction with optimum productivity is of vital importance for large-scale industrial production. Experimental procedures at room temperature are the mildest reaction conditions (essentially required for many temperature-sensitive organic substrates as a key step in multi-step sequence reactions) and are the core of mechanochemical organic synthesis. This green synthetic method is now emerging in a very progressive manner and until now, there is no book that reviews the recent developments in this area. Features cutting-edge research in the field of mechanochemical organic synthesis for more sustainable reactions Integrates advances in green chemistry research into industrial applications and process development Focuses on designing techniques in organic synthesis directed toward mild reaction conditions Includes global coverage of mechanochemical synthetic protocols for the generation of organic compounds

Download or read book Microwave Assisted Organic Synthesis written by Jason Tierney and published by John Wiley & Sons. This book was released on 2009-02-12 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first reports on the application of microwaves in organicsynthesis date back to 1986, but it was not until the recentintroduction of specifically designed and constructed equipment,which countered the safety and reproducibility concerns, thatsynthetic application of microwaves has become established as alaboratory technique. Microwave assisted synthesis is now beingadopted in many industrial and academic laboratories to takeadvantage of the novel chemistry that can be carried out using avariety of organic reaction types. This book demonstrates the underlying principles of microwavedielectric heating and, by reference to a range of organic reactiontypes, it's effective use in synthetic organic chemistry. Toillustrate the impact microwave assisted organic synthesis can haveon chemical research, case studies drawn mainly from thepharmaceutical industry are presented.