Download or read book Oxidative Coupling of Phenols written by William I. Taylor and published by . This book was released on 1967 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Mechanism of Phenolic Oxidative Coupling Reactions written by Patrick Doyle McDonald and published by . This book was released on with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies in Non phenolic Oxidative Coupling written by H. M. L. Davies and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthetic and Natural Phenols written by J.H.P. Tyman and published by Elsevier. This book was released on 1996-08-21 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of phenols tends to be ignored in organic chemical textbooks and to be lost amongst the many classes of functional derivatives. This volume is not intended to provide a textbook approach but rather to give an account of developments in phenol chemistry in the last two decades. Features of this book: • Numerous phenolic systems have been covered in detail, e.g. phenolic propanoids. • The emphasis throughout has been on synthesis, on what can be achieved by the use of phenolic intermediates and in the construction of phenolic end products. • Many chapters enable the reader to refer to the original literature wherever possible. • Various chapters provide a fund of tutorial material and problems for undergraduate studies and further, which will encourage perusal of the literature. Some 2000 references to applied and academic papers are given. Phenols are ubiquitous substances and now it is more widely accepted that there are pros and cons connected with their usage. The pros for compounds are well-known and are illustrated by perennial panaceas such as aspirin, paracetamol, codeine, etc. The cons are less obvious because they are also materials deeply entrenched in our standard of living and in most cases inherent hazards have only recently come to light. The book will be of interest to postgraduate students in academic and industrial work.
Download or read book Phenolic Oxidative Coupling written by Wesley Kwan Mung Chong and published by . This book was released on 1983 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various hypervalent iodine compounds were evaluated as reagents for intramolecular phenolic oxidative coupling. It was found that phenyliodine(III) bis(trifluoroacetate) was effective for the coupling of the monophenolic substrate 13a to 14a under neutral conditions. Vanadium oxytrifluoride and hypervalent iodine compounds were compared as oxidants for the conversion of 32 to 33. In an approach directed at a synthesis of pretazettine (17), phenacylamine 57 was elaborated in two steps to oxazole 50. However, this did not undergo catalytic hydrogenation to the desired oxazolidine 47. Oxazoline 60 proved to be too labile to be isolated upon dehydration of 65, which was prepared from di-octopamine (64) and the acid chloride of piperonylic acid (58). Finally, 64 and piperonal (69) were condensed and treated with ethyl chloroformate to provide trans-2,5-diaryloxazolidine 73. However, the latter was hydrolyzed under coupling conditions. Alternatively, when octopamine and piperonal were condensed and hydrogenated, amine 74 was obtained, which was in turn reacted with 1,1'-carbonyldiimidazole (75) to furnish the 2-oxazolidinone 76. Exposure of 76 to vanadium oxytrifluoride led to 78, which apparently arose from an undesired, spontaneous rear- rangement of the coupling product 77. Attempts to synthesize ether 79 starting with synephrine (81), 2-nitrostyrenes 86, and 4-hydroxymandelates 90 are described. The oxazolidine 97 was prepared from the condensation of synephrine 81 and treated with methyl chioroformate in the presence of methanol to afford acetal 100 in 71% yield. Phenyliodine(III) bis- (trifluoroacetate) was employed to couple 100 to 101 in 5 to 7% yield. Hydrolysis of the urethane moiety of 101 with potassium hydroxide in ethylene glycol gave the amine 105, which underwent a spontaneous cyclization to 107. Formation of the unnatural, cis B-D ring fusion stereochemistry in this ring closure was ascertained by nuclear magnetic resonance spectroscopy.
Download or read book Regio and Stereoselectivity of Oxidative Coupling Reaction of Phenols written by Harri Setälä and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dimeric phenolic compounds -- lignans and dilignols -- form in the so-called oxidative coupling reaction of phenols. Enzymes such as peroxidases and laccases catalyze the reaction using hydrogen peroxide or oxygen, respectively, as oxidant generating phenoxy radicals which couple together according to certain rules. In this thesis, the effects of the structures of starting materials -- monolignols -- and the effects of reaction conditions such as pH and solvent system on this coupling mechanism and on its regio- and stereoselectivity have been studied. After the primary coupling of two phenoxy radicals a very reactive quinone methide intermediate is formed. This intermediate reacts quickly with a suitable nucleophile which can be, for example, an intramolecular hydroxyl group or another nucleophile such as water, methanol, or a phenolic compound in the reaction system. This reaction is catalyzed by acids. After the nucleophilic addition to the quinone methide, other hydrolytic reactions, rearrangements, and elimination reactions occur, leading finally to stable dimeric structures called lignans or dilignols. Similar reactions occur also in the so-called lignification process when monolignol (or dilignol) reacts with the growing lignin polymer. New kinds of structures have been observed in this thesis. The dimeric compounds with a so-called spirodienone structure have been observed to form both in the dehydrodimerization of methyl sinapate and in the [beta]-1-type crosscoupling reaction of two different monolignols. This [beta]-1-type dilignol with a spirodienone structure was the first synthesized and published dilignol model compound, and at present, it has been observed to exist as a fundamental construction unit in lignins. The enantioselectivity of the oxidative coupling reaction was also studied for obtaining enantiopure lignans and dilignols. A rather good enantioselectivity was obtained in the oxidative coupling reaction of two monolignols with chiral auxiliary substituents using peroxidase/H2O2 as an oxidation system. This observation was published as one of the first enantioselective oxidative coupling reaction of phenols. Pure enantiomers of lignans were also obtained by using chiral cryogenic chromatography as a chiral resolution technique. This technique was shown to be an alternative route to obtain enantiopure lignans or lignin model compounds in a preparative scale.
Download or read book Oxidative Coupling of Phenols written by David Frederick Bowman and published by . This book was released on 1967 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oxidative Coupling of Phenols in Natural Product Biosynthesis written by Mervin Charles Hamblin and published by . This book was released on 1963 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies on the Oxidative Coupling of Phenols written by Alexander Henry Todd and published by . This book was released on 1964 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Phenolic Oxidative Coupling Reaction in the Synthesis of Morphine Alkaloids written by Douglas G. Vanderlaan and published by . This book was released on 1984 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oxidative Cross Coupling Reactions written by Aiwen Lei and published by John Wiley & Sons. This book was released on 2016-08-12 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first handbook on this emerging field provides a comprehensive overview of transition metal-catalyzed coupling reactions in the presence of an oxidant. Following an introduction to the general concept and mechanism of this reaction class, the team of authors presents chapters on C-C cross-coupling reactions using organometallic partners, C-Heteroatom bond forming reactions via oxidative couplings, and C-H couplings via C-H activation. The text also covers such groundbreaking topics as recent achievements in the fields of C-C and C-X bond formation reactions as well as C-H activation involving oxidative couplings. With its novel and concise approach towards important building blocks in organic chemistry and its focus on synthetic applications, this handbook is of great interest to all synthetic chemists in academia and industry alike.
Download or read book Oxidative Coupling of Phenols written by R. T. Martin and published by . This book was released on 1978 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Phenolic Compounds written by Marcos Soto-Hernández and published by BoD – Books on Demand. This book was released on 2017-03-15 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phenolic compounds as a large class of metabolites found in plants have attracted attention since long time ago due to their properties and the hope that they will show beneficial health effects when taken as dietary supplements. This book presents the state of the art of some of the natural sources of phenolic compounds, for example, medicinal plants, grapes or blue maize, as well as the modern methods of extraction, quantification, and identification, and there is a special section discussing the treatment, removal, and degradation of phenols, an important issue in those phenols derived from the pharmaceutical or petrochemical industries.
Download or read book Oxidative Coupling of Phenols on Activated Carbon written by Radisav D. Vidic and published by . This book was released on 1992 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Natural Product Biosynthesis written by Christopher T. Walsh and published by Royal Society of Chemistry. This book was released on 2017-04-28 with total page 787 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook describes the types of natural products, the biosynthetic pathways that enable the production of these molecules, and an update on the discovery of novel products in the post-genomic era.
Download or read book Oxidative Coupling of Phenols Edited by W I Taylor and A R Battersby written by and published by . This book was released on 1967 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic studies of the oxidative coupling polymerization of phenols written by Frits J. Viersen and published by . This book was released on 1988 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
