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Functionalization of Heterocycles: a Metal Catalyzed Approach Via
FUNCTIONALIZATION OF HETEROCYCLES: A METAL CATALYZED APPROACH VIA ALLYLATION AND C-H ACTIVATION A Dissertation Submitted to the Graduate Faculty of the North Dakota State University of Agriculture and Applied Science By Sandeepreddy Vemula In Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Department: Chemistry and Biochemistry October 2018 Fargo, North Dakota North Dakota State University Graduate School Title FUNCTIONALIZATION OF HETEROCYCLES: A METAL CATALYZED APPROACH VIA ALLYLATION AND C-H ACTIVATION By Sandeepreddy Vemula The Supervisory Committee certifies that this disquisition complies with North Dakota State University’s regulations and meets the accepted standards for the degree of DOCTOR OF PHILOSOPHY SUPERVISORY COMMITTEE: Prof. Gregory R. Cook Chair Prof. Mukund P. Sibi Prof. Pinjing Zhao Prof. Dean Webster Approved: November 16, 2018 Prof. Gregory R. Cook Date Department Chair ABSTRACT The central core of many biologically active natural products and pharmaceuticals contain N-heterocycles, the installation of simple/complex functional groups using C-H/N-H functionalization methodologies has the potential to dramatically increase the efficiency of synthesis with respect to resources, time and overall steps to key intermediate/products. Transition metal-catalyzed functionalization of N-heterocycles proved as a powerful tool for the construction of C-C and C-heteroatom bonds. The work in this dissertation describes the development of palladium catalyzed allylation, and the transition metal catalyzed C-H activation for selective functionalization of electron deficient N-heterocycles. Chapter 1 A thorough study highlighting the important developments made in transition metal catalyzed approaches for C-C and C-X bond forming reactions is discussed with a focus on allylation, directed indole C-2 substitution and vinylic C-H activation. -
Sonogashira Coupling Reaction in Water Using a Polymer-Supported Terpyridine–Palladium Complex Under Aerobic Conditions
Trans. Mat. Res. Soc. Japan 40[2] 103-106 (2015) Sonogashira Coupling Reaction in Water Using a Polymer-Supported Terpyridine–Palladium Complex under Aerobic Conditions Toshimasa Suzuka,* Mika Adachi, and Kazuhito Ogihara Department of Chemistry, Biology and Marine Science, University of the Ryukyus, Nishihara Okinawa 903-0213, Japan Fax: 81-098-895-8531, e-mail: [email protected] The palladium-catalyzed coupling reaction between an aryl halide and a terminal alkyne, the so-called Sonogashira coupling reaction, was found to occur in water under copper-free conditions using an amphiphilic polystyrene–poly(ethylene glycol) (PS-PEG) resin-supported palladium–terpyridine complex, giving the corresponding aryl-substituted alkyne in high yield. The PS-PEG resin-supported palladium–terpyridine catalyst was recovered simply by filtering the product mixture under air and could be reused three times with only slightly decreased catalytic activity after each use. Key words: Sonogashira, palladium, terpyridine, water, cross-coupling 1. INTRODUCTION organic solvent or metal-contaminated wastes are The palladium-catalyzed coupling reaction produced; and (2) the presence of oxygen and between an aryl halide and a terminal alkyne, the moisture do not negatively affect the reaction. so-called Sonogashira reaction [1], is recognized These benefits therefore allow the Sonogashira as being the most successful method for forming coupling reaction to be performed meeting the an sp2 carbon–sp3 carbon bond. Since its requirements of “green chemistry”. discovery by Sonogashira and co-workers in 1975, a vast amount of research has been performed cat 1. ( 5mol% Pd) into its synthetic applications and on improving X + R1 R1 the reaction efficiency [2]. -
Advances in Cross-Coupling Reactions
molecules Editorial Advances in Cross-Coupling Reactions José Pérez Sestelo * and Luis A. Sarandeses * Centro de Investigaciones Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, E-15071 A Coruña, Spain * Correspondence: [email protected] (J.P.S.); [email protected] (L.A.S.); Tel.: +34-881-012-041 (J.P.S.); +34-881-012-174 (L.A.S.) Received: 28 September 2020; Accepted: 30 September 2020; Published: 1 October 2020 Cross-coupling reactions stand among the most important reactions in chemistry [1,2]. Nowadays, they are a highly valuable synthetic tool used for the preparation of a wide variety of organic compounds, from natural and synthetic bioactive compounds to new organic materials, in all fields of chemistry [3]. Almost 50 years from its discovery, the research in this topic remains active, and important progresses are accomplished every year. For this reason, we believe that a Special Issue on this topic is of general interest for the chemistry community. Advances in cross-coupling reactions have been developed with the aim to expand the synthetic utility of the methodology, through the involvement of new components, reaction conditions, and therefore, novel synthetic applications [4]. Although initially the term “cross-coupling” referred to the reaction of an organometallic reagent with an unsaturated organic halide or pseudohalide under transition metal catalysis, currently the definition is much more general and applies to reactions involving other components, conditions, and more complex synthetic transformations. In addition to the well-known and recognized cross-coupling reactions using organoboron (Suzuki-Miyaura), organotin (Stille), organozinc (Negishi), or organosilicon (Hiyama) nucleophiles, reactions involving other organometallic reagents such as organoindium [5,6], organolithium [7], and Grignard reagents [8] are now useful synthetic alternatives. -
Multimetallic Catalysed Radical Oxidative C(Sp3)–H/C(Sp)–H Cross-Coupling Between Unactivated Alkanes and Terminal Alkynes
ARTICLE Received 2 Jan 2016 | Accepted 19 Apr 2016 | Published 24 Jun 2016 DOI: 10.1038/ncomms11676 OPEN Multimetallic catalysed radical oxidative C(sp3)–H/C(sp)–H cross-coupling between unactivated alkanes and terminal alkynes Shan Tang1, Pan Wang1, Haoran Li1 & Aiwen Lei1,2 Radical involved transformations are now considered as extremely important processes in modern organic synthetic chemistry. According to the demand by atom-economic and sustainable chemistry, direct C(sp3)–H functionalization through radical oxidative coupling represents an appealing strategy for C–C bond formations. However, the selectivity control of reactive radical intermediates is still a great challenge in these transformations. Here we show a selective radical oxidative C(sp3)–H/C(sp)–H cross-coupling of unactivated alkanes with terminal alkynes by using a combined Cu/Ni/Ag catalytic system. It provides a new way to access substituted alkynes from readily available materials. Preliminary mechanistic studies suggest that this reaction proceeds through a radical process and the C(sp3)–H bond cleavage is the rate-limiting step. This study may have significant implications for controlling selective C–C bond formation of reactive radical intermediates by using multimetallic catalytic systems. 1 College of Chemistry and Molecular Sciences, Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, China. 2 National Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, China. Correspondence and requests for materials should be addressed to A.L. (email: [email protected]). NATURE COMMUNICATIONS | 7:11676 | DOI: 10.1038/ncomms11676 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/ncomms11676 ubstituted alkynes are fundamental structural motifs in been developed through normal cross-dehydrogenative numerous natural products, bioactive molecules and coupling33 pathway (Fig. -
Recent Advances in Microwave-Assisted Copper-Catalyzed Cross-Coupling Reactions
catalysts Review Recent Advances in Microwave-Assisted Copper-Catalyzed Cross-Coupling Reactions Younis Baqi Department of Chemistry, College of Science, Sultan Qaboos University, P.O. Box 36, Muscat 123, Oman; [email protected]; Tel.: +968-2414-1473 Abstract: Cross-coupling reactions furnishing carbon–carbon (C–C) and carbon–heteroatom (C–X) bond is one of the most challenging tasks in organic syntheses. The early developed reaction protocols by Ullmann, Ullman–Goldberg, Cadiot–Chodkiewicz, Castro–Stephens, and Corey–House, utilizing elemental copper or its salts as catalyst have, for decades, attracted and inspired scientists. However, these reactions were suffering from the range of functional groups tolerated as well as severely restricted by the harsh reaction conditions often required high temperatures (150–200 ◦C) for extended reaction time. Enormous efforts have been paid to develop and achieve more sustainable reaction conditions by applying the microwave irradiation. The use of controlled microwave heating dramatically reduces the time required and therefore resulting in increase in the yield as well as the efficiency of the reaction. This review is mainly focuses on the recent advances and applications of copper catalyzed cross-coupling generation of carbon–carbon and carbon–heteroatom bond under microwave technology. Keywords: cross-coupling reaction; Cu catalyst; microwave irradiation; methodology; synthesis 1. Introduction Carbon–carbon (C–C) and carbon–heteroatom (C–X) bond formations through cross- Citation: Baqi, Y. Recent Advances in coupling reactions represents as one of the most useful strategy in the synthetic organic Microwave-Assisted chemistry, hence many procedures and methodologies have been developed and published Copper-Catalyzed Cross-Coupling in the literature. -
New Trends in C–C Cross-Coupling Reactions: the Use of Unconventional Conditions
molecules Review New Trends in C–C Cross-Coupling Reactions: The Use of Unconventional Conditions Marta A. Andrade and Luísa M. D. R. S. Martins * Centro de Química Estrutural and Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; [email protected] * Correspondence: [email protected]; Tel.: +35-121-841-9389 Academic Editor: Giuseppe Cirillo Received: 30 October 2020; Accepted: 20 November 2020; Published: 24 November 2020 Abstract: The ever-growing interest in the cross-coupling reaction and its applications has increased exponentially in the last decade, owing to its efficiency and effectiveness. Transition metal-mediated cross-couplings reactions, such as Suzuki–Miyaura, Sonogashira, Heck, and others, are powerful tools for carbon–carbon bond formations and have become truly fundamental routes in catalysis, among other fields. Various greener strategies have emerged in recent years, given the widespread popularity of these important reactions. The present review comprises literature from 2015 onward covering the implementation of unconventional methodologies in carbon–carbon (C–C) cross-coupling reactions that embodies a variety of strategies, from the use of alternative energy sources to solvent- free and green media protocols. Keywords: cross-coupling reactions; microwave irradiation; ultrasounds; mechanochemistry; solvent-free; water; ionic liquids; deep eutectic solvents; sustainability 1. Introduction Cross-coupling reactions have attracted and inspired researchers in the academia and industry for decades, given its significance as a synthetic tool in modern organic synthesis. The continuous interest in cross-coupling reactions, with more than 40 years of history, has been mostly driven by its valuable contributions and applications in the medicinal and pharmaceutical industries. -
A. Discovery of Novel Reactivity Under the Sonogashira Reaction Conditions B. Synthesis of Functionalized Bodipys and BODIPY-Sug
A. Discovery of novel reactivity under the Sonogashira reaction conditions B. Synthesis of functionalized BODIPYs and BODIPY-sugar conjugates Ravi Shekar Yalagala, M.Phil Department of Chemistry Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Faculty of Mathematics and Science, Brock University St. Catharines, Ontario © 2016 ABSTRACT A. During our attempts to synthesize substituted enediynes, coupling reactions between terminal alkynes and 1,2-cis-dihaloalkenes under the Sonogashira reaction conditions failed to give the corresponding substituted enediynes. Under these conditions, terminal alkynes underwent self-trimerization or tetramerization. In an alternative approach to access substituted enediynes, treatment of alkynes with trisubstituted (Z)- bromoalkenyl-pinacolboronates under Sonogashira coupling conditions was found to give 1,2,4,6-tetrasubstituted benzenes instead of Sonogashira coupled product. The reaction conditions and substrate scopes for these two new reactions were investigated. B. BODIPY core was functionalized with various functional groups such as nitromethyl, nitro, hydroxymethyl, carboxaldehyde by treating 4,4-difluoro-1,3,5,7,8- pentamethyl-2,6-diethyl-4-bora-3a,4a-diaza-s-indacene with copper (II) nitrate trihydrate under different conditions. Further, BODIPY derivatives with alkyne and azido functional groups were synthesized and conjugated to various glycosides by the Click reaction under the microwave conditions. One of the BODIPY–glycan conjugate was found to form liposome upon rehydration. The photochemical properties of BODIPY in these liposomes were characterized by fluorescent confocal microscopy. ii ACKNOWLEDGEMENTS I am extremely grateful to a number of people. Without their help, this document would have never been completed. First and foremost, I would like to thank my supervisor and mentor Professor Tony Yan for his guidance and supervision to make the thesis possible. -
Novel Microbiocides
(19) TZZ _Z__T (11) EP 2 641 901 A1 (12) EUROPEAN PATENT APPLICATION (43) Date of publication: (51) Int Cl.: 25.09.2013 Bulletin 2013/39 C07D 215/40 (2006.01) C07D 401/12 (2006.01) A61K 31/4709 (2006.01) A01N 43/42 (2006.01) (21) Application number: 12160780.8 (22) Date of filing: 22.03.2012 (84) Designated Contracting States: (72) Inventor: The designation of the inventor has not AL AT BE BG CH CY CZ DE DK EE ES FI FR GB yet been filed GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR (74) Representative: Herrmann, Jörg Designated Extension States: Syngenta Crop Protection BA ME Münchwilen AG Intellectual Property Department (71) Applicant: Syngenta Participations AG Schaffhauserstrasse 4058 Basel (CH) 4332 Stein (CH) (54) Novel microbiocides (57) The invention relates to compounds of formula I wherein R1, R2, X, Y1, Y2, Y3, D1, D2, D3, G1, G2, G3 and p are as defined in the claims. The invention further provides intermediates used in the preparation of these compounds, to compositions which comprise these compounds and to theiruse in agriculture or horticulture for controlling orpreventing infestation of plants by phytopathogenic microorganisms, preferably fungi. EP 2 641 901 A1 Printed by Jouve, 75001 PARIS (FR) EP 2 641 901 A1 Description [0001] The present invention relates to novel microbiocidally active, in particular fungicidally active, cyclic bisoxime derivatives. Itfurther relatesto intermediates used inthe preparationof these compounds, to compositions which comprise 5 these compounds and to their use in agriculture or horticulture for controlling or preventing infestation of plants by phytopathogenic microorganisms, preferably fungi. -
Mediated Azide-Alkyne Cycloaddition Reactions Using Chelating Azides Wendy S
Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2012 Development of Copper(II)-Mediated Azide-Alkyne Cycloaddition Reactions Using Chelating Azides Wendy S. Brotherton Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES DEVELOPMENT OF COPPER(II)-MEDIATED AZIDE-ALKYNE CYCLOADDITION REACTIONS USING CHELATING AZIDES By WENDY S. BROTHERTON A Dissertation submitted to the Department of Chemistry and Biochemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Spring Semester, 2012 Wendy S. Brotherton defended this dissertation on December 8, 2011. The members of the supervisory committee were: Lei Zhu Professor Directing Dissertation P. Bryant Chase University Representative Gregory B. Dudley Committee Member Igor V. Alabugin Committee Member Michael G. Roper Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with university requirements. ii This manuscript is dedicated to my mother for all of her encouragement and sacrifices over the many years of my education. I would also like to dedicate this to my fiancé, Travis Ambrose, who has been so supportive and encouraging throughout this entire process. iii ACKNOWLEDGEMENTS I would like to thank Professor Lei Zhu for his guidance, support and assistance over the course of my graduate studies. I would like to express my gratitude to the past and present members of the Zhu group for their support and friendship over the years: Dr. -
Synthesis of Silsesquioxanes with Substituted Triazole Ring Functionalities and Their Coordination Ability †
molecules Article Synthesis of Silsesquioxanes with Substituted Triazole Ring Functionalities and Their Coordination Ability † Monika Rzonsowska 1,2,* , Katarzyna Kozakiewicz 1, Katarzyna Mituła 1,2 , Julia Duszczak 1,2, Maciej Kubicki 3 and Beata Dudziec 1,2,* 1 Department of Organometallic Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Pozna´n, Uniwersytetu Pozna´nskiego8, 61-614 Pozna´n,Poland; [email protected] (K.K.); [email protected] (K.M.); [email protected] (J.D.) 2 Centre for Advanced Technologies, Adam Mickiewicz University in Pozna´n,Uniwersytetu Pozna´nskiego10, 61-614 Pozna´n,Poland 3 Faculty of Chemistry, Adam Mickiewicz University in Pozna´n,Uniwersytetu Pozna´nskiego8, 61-614 Pozna´n,Poland; [email protected] * Correspondence: [email protected] (M.R.); [email protected] (B.D.); Tel.: +48-618291878 (B.D.) † Dedicated to Professor Julian Chojnowski on the occasion of his 85th birthday. Abstract: A synthesis of a series of mono-T8 and difunctionalized double-decker silsesquioxanes bearing substituted triazole ring(s) has been reported within this work. The catalytic protocol for their formation is based on the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) process. Diverse alkynes were in the scope of our interest—i.e., aryl, hetaryl, alkyl, silyl, or germyl—and the latter was shown to be the first example of terminal germane alkyne which is reactive in the applied process’ conditions. From the pallet of 15 compounds, three of them with pyridine-triazole and Citation: Rzonsowska, M.; thiophenyl-triazole moiety attached to T8 or DDSQ core were verified in terms of their coordinating Kozakiewicz, K.; Mituła, K.; properties towards selected transition metals, i.e., Pd(II), Pt(II), and Rh(I). -
Recollections of Organopalladium Chemistry*
Pure Appl. Chem., Vol. 71, No. 8, pp. 1539±1547, 1999. Printed in Great Britain. q 1999 IUPAC Recollections of organopalladium chemistry* Jiro Tsuji Emeritus Professor, Tokyo Institute of Technology, Tsu 602±128, Kamakura, Japan Abstract: Organopalladium chemistry has 40 years' history. It was born in late 1950s by the invention of the Wacker process. Inspired by the Wacker reaction, we discovered the ®rst example of the carbon±carbon bond formation by means of a Pd complex, and opened the ®eld of p-allylpalladium chemistry. Historical account of organopalladium chemistry, and major accomplishments in our laboratory in 1960s are presented. INTRODUCTION Invention of the Wacker process to produce acetaldehyde using PdCl2±CuCl2 as catalysts in 1959 is the ®rst example of the homogeneous palladium-catalyzed reaction [1]. Soon after the invention of the Wacker process, formation of vinyl acetate by the oxidative acetoxylation of ethylene with PdCl2 in AcOH in the presence of NaOAc was reported by Moiseev [2]. Vinyl acetate is now produced commercially based on this reaction using supported Pd catalyst in a gas phase (Scheme 1). Scheme 1 As mechanistic explanation of the formation of acetaldehyde, Smidt and co-workers made the following statement in their review [1]. `Nucleophilic attack on ole®n and hydride transfer are characteristic for this reaction. The oxygen required for the oxidation of the ole®n is provided by the water. According to our hypothesis only the oxygen atom of the water is transferred to the ole®n, while the four hydrogen atoms originally present in ethylene remain there.' The early 1960s was the dawn of the research on OMCOS. -
A Mild Aqueous Sonogashira Reaction As a Fluorescent Labeling Strategy for 5-Bromide-20-Deoxyuridine
molecules Article A Mild Aqueous Sonogashira Reaction as a Fluorescent Labeling Strategy for 5-Bromide-20-Deoxyuridine Shufang Wang 1, Yongxin Gao 2, Shigang Shen 3, Hui Wen 1 and Huaqing Cui 1,* ID 1 State Key Laboratory of Bioactive Substances and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, China; [email protected] (S.W.); [email protected] (H.W.) 2 Beijing Key Laboratory of Active Substances Discovery and Drugability Evaluation, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, China; [email protected] 3 Key Lab of Analytical Science and Technology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Baoding 071000, China; [email protected] * Correspondence: [email protected]; Tel.: +86-10-6303-7952 Received: 15 December 2017; Accepted: 11 January 2018; Published: 12 January 2018 Abstract: C5-modified uridines are a valuable class of nucleoside analogues, both as potent chemotherapy agents and through their use as the conjunction site in DNA labeling strategies. As an important C5-modified uridine, BrdU has been used in cell proliferation assays since the 1980s. Currently, the detection of BrdU relies on traditional immunostaining; however, this approach has its limitations. Thus, it is desirable, albeit difficult, to develop chemistry methods to fluorescently label BrdU in a cellular context. In the present study, we report our efforts toward developing a robust chemistry methodology for BrdU fluorescent labeling. The Sonogashira reaction was chosen as the key reaction, and various alkynyl groups (aliphatic or aryl) containing fluorescent dyes were synthesized to cross-couple with BrdU.