DOCSLIB.ORG

Investigation of PEPPSI Precatalysts for Controlled Polymerization of Π-Conjugated Polymers from Cheap Starting Materials

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Investigation of PEPPSI Precatalysts for Controlled Polymerization of Π-Conjugated Polymers from Cheap Starting Materials Investigation of PEPPSI precatalysts for controlled polymerization of π-conjugated polymers from cheap starting materials Thesis submitted in partial fulfilment of the requirement for a degree of Doctor of Philosophy at the University of London Benjamin John Groombridge Page | 1 Acknowledgements I would firstly like to thank my supervisors, Dr. Igor Larrosa and Dr. Stephen M. Goldup, for giving me the opportunity to carry out the research described in this thesis. Special gratitude to both of you, for the invaluable expert guidance and support during my PhD. I would like to thank the following people for the words of wisdom and practical input during the course of my PhD: Prof. Mike Watkinson, Dr. Chris Bray, Dr. Joby Winn, Dr. Jamie Lewis, Dr. Catherine Fletcher, Dr. Saidul Islam, Dr. Xacobe Couso Cambeiro, Dr. Nanna Ahlsten, Dr. Paolo Ricci, Dr. Carlos Arróniz, Dr. Sara Preciado, Dr. Francisco Juliá-Hernández, Dr. Josep Cornella, Dr. Tanya Boorman, Dr. Saidul Islam, Robert Bordoli, Ed Neal, Jessica Pancholi, Katrina Krämer, Rachel Grainger, Marco Simonetti, Junfei Luo, Adam Johnston, Gregory Perry and Nicky Willis. The research described would not have been possible without the fantastic support from both NMR and analytic services in particular Dr. Harold Toms and Dr. Ian Sanders. Finally, I would like to thank my friends and family for their support and advice throughout my PhD and during the writing up period. Page | 2 Declaration I declare that the scientific work presented in this thesis is my own and was carried out in the School of Biological and Chemical Science at Queen Mary, University of London between September 2010 and September 2014. No part of this work has been submitted in support of an application for another degree or qualification at this University or any other institution of learning. Signature: _____________________ Date: _____________________ Page | 3 Abstract Since the discovery of catalyst-transfer polymerization in 2004 there has been significant research into expanding the scope from Kumada couplings of poly-thiophenes mediated by nickel initiators. This thesis presents an investigation toward the synthesis of π-conjugated polymers by the elusive pseudo-living polymerization of chloroarene monomers. Chapter 1 sets the scene with an in-depth review of chain-growth polymerizations mediated by palladium catalysts. In chapter 2, we report the first examples of exhaustive substitution of poly-chloroarenes in the presence of a deficit of nucleophile in the sp 3-sp 2 Negishi coupling mediated by PEPPSI-IPr. These experiments demonstrated intramolecular transfer of the active catalyst which is essential for catalyst-transfer polymerization. Chapter 3 describes the synthesis of the highly active PEPPSI-IPent precatalyst from cheap commercially available starting materials with minimal purification. Subsequently in chapter 4, it was demonstrated that PEPPSI-IPent undergoes exhaustive substitution of poly-chloroarenes in the presence of a deficit of nucleophile in sp 2-sp 2 Kumada, Negishi and Suzuki cross-couplings. In chapter 5, optimization of current Kumada polymerization of bromo phenylene-based monomer mediated by PEPPSI-IPr is described. Direct comparison of model reactions and Kumada polycondensation confirmed high selectivity for exhaustive substitution is required to achieve polycondensation in a chain-growth manner. Initial research into catalyst-transfer polycondensation of chloroarene monomers did not achieve polymerization in a chain-growth manner using modified conditions from bromoarene monomers. Page | 4 Table of Contents Acknowledgements .............................................................................................................. 2 Declaration ........................................................................................................................... 3 Abstract ................................................................................................................................ 4 List of abbreviations .......................................................................................................... 11 1.0 Chapter 1 - Introduction 1.1 Polymers ...................................................................................................................... 13 1.2 Statistical terms ............................................................................................................ 13 1.3 Synthetic methods ........................................................................................................ 15 1.3.1 Step growth polymerizations ................................................................................. 15 1.3.2 Chain growth polymerizations .............................................................................. 17 1.3.2.1 Radical chain growth polymerizations ........................................................... 18 1.3.3 Living polymerization ........................................................................................... 20 1.3.3.1 Ionic polymerizations..................................................................................... 21 1.3.3.2 Chain growth polycondensation .................................................................... 22 1.3.3.3 Coordination polymerization ......................................................................... 23 1.4 π-Conjugated polymers ................................................................................................ 24 1.4.1 Selected applications of conjugated polymers ...................................................... 26 1.4.2 Synthesis of conjugated polymers ......................................................................... 27 1.4.3.1 Discovery of catalyst transfer polycondensation ........................................... 28 1.4.3.2 Model reactions to identify intramolecular oxidative addition ...................... 29 1.4.3.3 Mechanism of catalyst transfer polymerization ............................................. 30 1.4.3.4 Examples of Nickel Mediated Catalyst Transfer Polymerization .................. 31 1.4.3.3 Scope and limitations of Nickel mediated chain transfer polymerization ..... 33 Page | 5 1.4.4 Palladium and chain growth polymerization .................................................... 34 1.4.4.1 Model reactions to identify intramolecular oxidative addition with palladium catalysts ...................................................................................................................... 34 1.4.4.2 Catalyst-transfer polymerizations mediated by palladium catalysts .............. 37 1.4.4.3 Overview and outlook .................................................................................... 42 1.5. Model reactions mediated by PEPPSI-IPr .................................................................. 43 1.6 Chain growth polymerization mediated by PEPPSI-IPr .............................................. 47 1.7 Aims and Goals ............................................................................................................ 48 1.8 References .................................................................................................................... 49 2.0 Chapter 2 - Model reactions mediated by PEPPSI-IPr 2.1 Introduction .................................................................................................................. 55 2.2 Addition of functional groups to aryl dibromides........................................................ 55 2.3 Addition of functional groups to aryl dichlorides ........................................................ 56 2.4 Competition between aryl chlorides ............................................................................ 57 2.5 Poly-halogenated benzenes .......................................................................................... 59 2.6 Variation in reaction conditions ................................................................................... 61 2.6.1 Solvent ratio .......................................................................................................... 61 2.6.2 Temperature scan .................................................................................................. 62 2.6.3 Equivalents of 1,3-dichlorobenzene ...................................................................... 63 2.6.4 Catalyst loading ..................................................................................................... 64 2.6.5 Time Scan .............................................................................................................. 64 2.7 Conclusions .................................................................................................................. 65 2.8 References .................................................................................................................... 66 3.0 Chapter 3 - PEPPSI-IPent synthesis 3.1 Introduction .................................................................................................................. 68 Page | 6 3.2 Negishi coupling of 3-pentylzinc bromide .................................................................. 70 3.3 Route 1: Synthesis of aniline 33d ................................................................................ 72 3.4 Route 2: Synthesis of aniline 33d ................................................................................ 74 3.5 PEPPSI-IPent synthesis ..............................................................................................
Load more

Recommended publications
  • Advancing Conjugated Polymer Synthesis Through Catalyst Design
    Advancing Conjugated Polymer Synthesis Through Catalyst Design by Kendra Delaine Souther A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Chemistry) in the University of Michigan 2018 Doctoral Committee: Professor Anne J. McNeil, Chair Professor Jinsang Kim Professor John P. Wolfe Associate Professor Paul M. Zimmerman Kendra D. Souther [email protected] ORCID iD: 0000-0002-2373-1434 DEDICATION To my mother and father, Idalene and Garrison, for instilling the power of hardwork in me from a very young age and being a constant fountain of encouragement; lifting me up when I forget how. To my sister, Deidre, for making my world a brighter place; always making me laugh and for always having a prayer ready to fill me up with love. I love you all. MBT. ii ACKNOWLEDGEMENTS I must first begin by thanking my advisor and mentor, Professor Anne J. McNeil. Her commitment to pursuing challenging problems with integrity and fervor gave me a role model throughout my grad school experience and was a constant motivator. She encouraged me to be the best version of myself, for myself, and helped shape me into an independent scientist and problem solver. Next, I must thank my labmates past and present who made coming to work every day easy: Dr. Se Ryeon Lee, Dr. Kelsey Carter, Dr. Edmund Palermo, Dr. Fei Cheng, Dr. Zachary Bryan, Dr. Danielle Zurcher, Dr. Gesine Veits, Dr. Mitchell Smith, Dr. Peter Goldberg, Dr. Ariana Hall, Dr. Chen Kong, Amanda Leone, Matthew Hannigan, Justin Harris, Emily Mueller, Han Kim, Takunda Chazovachii, Dr.
    [Show full text]
  • Palladium-Catalysed Coupling Chemistry Palladium-Catalysed Coupling Chemistry
    Palladium-Catalysed Coupling Chemistry Palladium-Catalysed Coupling Chemistry Palladium catalysis has gained widespread use in industrial and academic synthetic chemistry laboratories as a powerful methodology for the formation of C-C and C-Heteroatom bonds. Several coupling reactions have been developed with different substrates: 1. SUZUKI-MIYAURA 2. STILLE 3. NEGISHI 4. KUMADA 5. HIYAMA 6. SONOGASHIRA 7. HECK 8. BUCHWALD-HARTWIG 9. CYANATION 10. CARBONYLATION 2 Understanding the catalytic cycle Most palladium catalysed reactions are believed to follow a similar catalytic cycle. The catalytic species can be formed in situ using a palladium source, such as Pd2(dba)3 or Pd(OAc)2 and the necessary ligand, or introduced as a preformed catalyst such as t Pd(PPh3)4 or Pd(P Bu3)2. Careful choice of ligand can facilitate two steps of the catalytic cycle. The use of strong σ-donating ligands, such as trialkylphosphines, increases electron density around the metal, accelerating the oxidative addition of the catalyst to the substrate. This is most commonly believed to be the rate determining step. Choice of ligand also determines the mechanism by which oxidative addition occurs.1 The elimination step is accelerated by the use of bulky ligands, in particular phosphine ligands exhibiting a large cone angle (also known as Tolman angle).2 Ligand Cone Angle (deg) Cat. No. dppm 121 29361 dppe 125 14791 dppp 127 31005 dcpe 142 36385 PPh3 145 14042 P(c-hex)3 170 42161 t P( Bu)3 182 36089 P(C6F5)3 184 31316 P(2,4,6-Me3C6H2)3 212 32113 3 Phosphine ligands have recently been replaced in a number of palladium cataly sed reactions with N-heterocyclic carbenes (NHCs).3 These ligands offer similar electronic properties to phosphines, being strongly σ-donating and weakly π-acidic.
    [Show full text]
  • Palladium-Catalyzed Cross-Couplings in Organic Synthesis
    Palladium-Catalyzed Cross-Couplings in Organic Synthesis 2010 Nobel Prize in Chemistry Professor Sambasivarao Kotha Department of Chemistry IIT-Bombay 400 076 http/www.chem.iitb.ac.in/~srk 12/28/10 1 "palladium-catalyzed cross couplings in organic synthesis” Richard F. Heck Ei-ichi Negishi Akira Suzuki University of Delaware Purdue University Hokkaido University USA West Lafayette Sapporo, Japan IN, USA B 1931 B 1935 B 1930 12/28/10 2 Heck, Negishi and Suzuki coupling in synthesis of fine chemicals Heck reaction O Si Si DVS-bis-BCM (electronic resin monomer) N O N Negishi Cl coupling N Cl HN O HN Suzuki coupling Serotonin agonist Boscalid 12/28/10 (fungiside) 3 Facts on the Nobel Prize in Chemistry On 27 November 1895, Alfred Nobel signed his last will and testament, giving the largest share of his fortune to a series of prizes, the Nobel Prizes. As described in Nobel's will one part was dedicated to “ the person who shall have made the most important chemical discovery or improvement”. http://nobelprize.org/nobel_prizes/chemistry/ 4 Number of Nobel Prizes in Chemistry 102 Nobel Prizes in Chemistry have been awarded since 1901. It was not awarded on eight occasions: in 1916, 1917, 1919, 1924, 1933, 1940, 1941 and 1942. Why were the Chemistry Prizes not awarded in those years? In the statutes of the Nobel Foundation it says: "If none of the works under consideration is found to be of the importance indicated in the first paragraph, the prize money shall be reserved until the following year. If, even then, the prize cannot be awarded, the amount shall be added to the Foundation's restricted funds." During World War I and II, fewer Nobel Prizes were awarded.
    [Show full text]
  • Desperately Seeking for the Catalytic Species in Suzuki-Miyaura Reaction Amine Bourouina
    Desperately Seeking For The Catalytic Species In Suzuki-Miyaura Reaction Amine Bourouina To cite this version: Amine Bourouina. Desperately Seeking For The Catalytic Species In Suzuki-Miyaura Reaction. Chemical and Process Engineering. Université de Lyon, 2019. English. NNT : 2019LYSE1258. tel-02482607 HAL Id: tel-02482607 https://tel.archives-ouvertes.fr/tel-02482607 Submitted on 18 Feb 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. N°d’ordre NNT : 2019LYSE1258 THESE de DOCTORAT DE L’UNIVERSITE DE LYON opérée au sein de l’Université Claude Bernard Lyon 1 Ecole Doctorale ED206 Ecole Doctorale de Chimie de Lyon Spécialité de doctorat : Discipline : Procédés Soutenue publiquement le 28/11/2019, par : Amine BOUROUINA Desperately Seeking For The Catalytic Species In Suzuki-Miyaura Reaction Devant le jury composé de : FERRIGNO Rosaria, Professeure des Universités, Université Lyon Présidente HII King Kuok (Mimi), Professeure, L'Imperial College de Londres Rapporteuse RIANT Olivier, Professeur ordinaire, Université Catholique de Louvain Rapporteur
    [Show full text]
  • Recent Advances of Modern Protocol for C-C Bonds—The Suzuki Cross-Coupling
    Advances in Chemical Engineering and Science, 2013, 3, 19-32 http://dx.doi.org/10.4236/aces.2013.33A1003 Published Online July 2013 (http://www.scirp.org/journal/aces) Recent Advances of Modern Protocol for C-C Bonds—The Suzuki Cross-Coupling Jadwiga Sołoducho*, Kamila Olech, Agnieszka Świst, Dorota Zając, Joanna Cabaj Faculty of Chemistry, Wrocław University of Technology, Wrocław, Poland Email: *[email protected] Received April 30, 2013; revised May 30, 2013; accepted June 30, 2013 Copyright © 2013 Jadwiga Sołoducho et al. This is an open access article distributed under the Creative Commons Attribution Li- cense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Over the past 20 years, small molecule solid phase synthesis has become a powerful tool in the discovery of novel mol- ecular materials. In the development of organic chemistry, the carbon-carbon bond formation has always been one of the most useful and fundamental reaction. The current review summarizes recent developments in metal-catalyzed cou- pling reactions. The following method is discussed in detail—the cross-coupling of aryl halides with aryl boronic acids (the Suzuki coupling), and the others C-C bond formation reactions as the palladium-catalyzed reaction between an aryl and (or) alkyl halide and a vinyl functionality (the Heck reaction); and the palladium-catalyzed cross-coupling reaction of organostannyl reagents with a variety of organic electrophiles (the Stille reaction)—are mentioned. Keywords: C-C Bond Formation; Coupling Reactions; Palladium Catalysts; Suzuki Coupling; Heterocyclic Copolymers 1. Introduction [4] reported that cross-coupling reactions between al- kenylboranes and organic halides were efficiently cata- Recently, small-molecule solid-phase synthesis has beco- lyzed by a catalytic amount of tetrakis (triphenylphoshine) me a powerful tool in the discovery of new drugs or mo- palladium (Pd(PPh ) ) in the presence of a suitable base.
    [Show full text]
  • Novel Reagents and Catalysts for Facilitating Synthesis Peppsi™: A
    NOVELPEppSI ™REAGE: A NENWTS GE ANNERATIOD CATALYSTSN OF AIR FOR-STA FABCLEILITATI Pd PNRECG SATALYSTSYNTHESIS VOL. 39,38, NO.NO.1 4 •• 20062005 ROM Polymerization in Facilitated Synthesis Pd–N-Heterocyclic CarbenePolyurea-Encapsulated (NHC) Catalysts for Cross-CouplingPalladium ReactionsCatalysts sigma-aldrich.com New Products from Aldrich R&D BD3–THF Solution Stabilized with NIMBA and Alkynylboronates Me-CBS Solutions in THF Alkynylboronates participate in a variety of regio- and stereoselective The asymmetric borane reduction of prochiral ketones catalyzed by (R)- carbon–carbon bond-forming reactions including enyne cross metathesis 1 2 3 or (S)-Me-CBS provides a facile method for accessing chiral secondary (CM), Alder-ene, and Dötz annulation reactions. Products obtained alcohols.1 We are pleased to introduce N-isopropyl-N-methyl-tert-butylamine from these reactions are either alkenyl or arylboronates, which are active coupling partners in (NIMBA) stabilized BD3–THF solutions for the preparation of isotopically 2 Suzuki and Heck CH3 labeled alcohols. Amine-stabilized borane–THF solutions exhibit enhanced BPin O CH3 shelf-life over those containing other stabilizers, and additionally, higher reactions. BPin = B R 3 O CH3 levels of enantiomeric excess are obtained. Deuterium-labeled alcohols CH3 may also be synthesized through (1) Kim, M.; Lee, D. O HO D the sequence of hydroboration– OBD3 Org. Lett. 2005, 7, CH3 CH3 1865. (2) (a) Hansen, R' R' Cr(CO) oxidation of olefins. Either method (R)-Me-CBS 5 R R E. C.; Lee, D. J. Am. H3CO [Ru]+ of alcohol preparation gives high Chem. Soc. 2005, 127, [Ru] levels of deuterium incorporation R Yield (%) ee (%)D atom % 3252.
    [Show full text]
  • Pharmacomodulation of Positions Two & Four of Nucleus Five
    Al Saadi et al (2019): Pharmacomodulation using palladium catalyze November 2019 Vol. 22(7) Pharmacomodulation of positions two & four of nucleus five-nitroimidazole by using palladium catalyze Noor Thamer Abbas Al Saadi 1* Marwah Thamer Abbas Al Saadi1, Zina Tahsin Ali1 1. College of pharmacy, Almuthanna University *Corresponding Author: Dr. Noor Thamer Abbas Al Saadi, College of pharmacy, Almuthanna University Email: [email protected] Abstract: Cross-coupling reactions consist of reactions between an electrophilic organic species such as a halide or a pseudohalide (triflate, tosylate, mesylate) (R1-X) and an organometallic reagent (R2-M; M = Mg, Li, Cu, Zn, Al, B and Si). These reactions are catalyzed by a metal transition complex based on nickel or palladium, and result in the formation of new CClO.sub.2 bonds. Many cross-coupling reactions have thus been developed in about twenty years, by varying the nature of the electrophile, organometallic reagent and transition metal (Scheme 1). The most commonly used coupling reactions involve palladium as a transition metal, and the diversity of these reactions is based on the type of organometallic used, based on aluminum, zinc or zirconium (Negishi coupling), [1] boron (Suzuki coupling), [2] magnesium (Kumada coupling), [3] tin (Stille coupling) , [4] or silicon (coupling of Hiyama) .[5] The development of this type of reaction allowed Richard Heck, Ei-ichi Negishi and Akira Suzuki to be awarded the Nobel Prize for Chemistry in 2010.[1]. Key words: Pharmacomodulation, nitromidazole, palladiumcatalyz, cross-coupling, reactions How to cite this article: Al Saadi NTA, Al Saadi MTA, Ali ZT (2019): Pharmacomodulation of positions two & four of nucleus five-nitroimidazole by using palladiumcatalyz, Ann Trop Med Pub Health; 22: S202.
    [Show full text]
  • A Robust Nickel Catalyst with an Unsymmetrical Propyl-Bridged Diphosphine Ligand for Catalyst-Transfer Polymerization
    Polymer Journal (2020) 52:83–92 https://doi.org/10.1038/s41428-019-0259-3 ORIGINAL ARTICLE A robust nickel catalyst with an unsymmetrical propyl-bridged diphosphine ligand for catalyst-transfer polymerization 1 1 1 2 1 Matthew A. Baker ● Josué Ayuso-Carrillo ● Martin R. M. Koos ● Samantha N. MacMillan ● Anthony J. Varni ● 1 1 Roberto R. Gil ● Kevin J. T. Noonan Received: 7 June 2019 / Revised: 9 July 2019 / Accepted: 30 July 2019 / Published online: 3 September 2019 © The Society of Polymer Science, Japan 2019 Abstract A new nickel diphosphine catalyst has been synthesized in which the bidentate ligand has two different phosphine donors, a typical PPh2 group and a stronger σ-donating PEt2 group. The catalyst was highly effective for the chain-growth polymerization of a 3-alkylthiophene monomer using a Suzuki–Miyaura cross-coupling. The catalyst is particularly effective for this polymerization in the presence of excess free ligand. The unsymmetrical diphosphine nickel complex reported here represents a new approach to tuning metal-ligand reactivity in the chain-growth polymerization of aromatic monomers. In addition, this new nickel catalyst exhibited increased hydrolytic resistance in the polymerization as compared to 1234567890();,: 1234567890();,: commercially available 1,3-bis(diphenylphosphino)propane nickel dichloride. Introduction relatively mild reaction conditions needed to promote C–C bond formation. While palladium complexes are often used Metal-catalyzed cross-couplings continue to be among the to catalyze this transformation [12–24], nickel catalysts most powerful strategies for forming C–C bonds, and they such as Ni(dppp)Cl2 and Ni(IPr)(PPh3)Cl2 can also be are commonly employed to synthesize π-conjugated poly- employed to polymerize X-Ar-B(OR)2 monomers [25, 26].
    [Show full text]
  • Umicore CX Catalysts Palladium Catalyzed Cross-Coupling Reactions 2 3
    Umicore CX Catalysts Palladium catalyzed cross-coupling reactions 2 3 Specific, well-defined precatalysts and ready-made catalysts UMICORE PMC WILL ASSIST YOU WITH OUR EXPERTISE IN ACTIVITY EXACTLY AS FAR AS IT IS NEEDED TO MEET YOUR NEEDS Palladium catalyzed C-C- and C-X bond forming reactions have undergone remarkable developments in the last 25 years [1]. Numerous research groups, inspired by the 2010 Chemistry Nobel Prize awardees Heck, Negishi and Suzuki [2], have developed new palladium precursors, ligands and catalysts to fully utilize this versatile, synthetic tool in organic chemistry. Some of these palladium complexes have transitioned into a broad range of applications spanning from synthesis of agrochemicals, use in natural products and active pharmaceutical ingredients down to appearing in materials for electronic applications. Umicore CX catalysts at glance: • Alternative Palladium precursors • Well-defined, ready-to-use Palladium phosphine complexes • Selective & active Palladium N-heterocyclic carbene complexes • Efficient Palladium recovery streams [1] a) Handbook of Organopalladium Chemistry for Organic Synthesis, (Eds.: E. Negishi, F. Diederich) Wiley-VCH, 2002, b) Metal-Catalyzed Cross Coupling Reactions, (Eds.: A. de Meijere, F. Diederich) Wiley-VCH, 2004, c) Angew. Chem. Int. Ed. 2012, 51, 5062 [2] http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2010/popular-chemistryprize2010.pdf 4 5 CROSS-COUPLING REACTIONS ARE A TRANSITION METAL CATALYZED COUPLING OF AN ORGANIC ELECTROPHILE (I.E. ORGANIC HALIDE) WITH
    [Show full text]
  • 1 Kumada Coupling [Mg]
    P. Wipf 1/30/2007 Kumada Coupling [Mg] Huang, J.; Nolan, S. P., "Efficient cross-coupling or aryl chlorides with aryl Grignard reagents (Kumada reaction) mediated by a palladium/imidazolium chloride system." J. Am. Chem. Soc. 1999, 121, 9889-9890. Stille Coupling [Sn] JOC 1991, 56, 2883. TH 1992, 48, 2957. Organometallics 1991, 10, 1993. 1 P. Wipf 1/30/2007 JACS 1984, 106, 7500: capnellene Negishi Coupling [Zn] Tius, M. A.; Gomez-Galeno, J.; Gu, X.; Zaidi, J. H., "C-glycosylanthraquinone synthesis: Total synthesis of vineomycinone B2 methyl ester." J. Am. Chem. Soc. 1991, 113, 5775-5783. 2 P. Wipf 1/30/2007 Wipf, P.; Lim, S. J. Am. Chem. Soc. 1995, 117, 558; Wipf, P.; Lim, S. Chimia 1996, 50, 157. Mori, Y.; Seki, M., "Highly efficient phosphine-free Pd(OAc)2-catalyzed Fukuyama coupling reaction: Synthesis of a key intermediate for (+)-biotin under low catalyst loading." Synlett 2005, 2233-2235. 3 P. Wipf 1/30/2007 Suzuki Coupling [B] esp. for biaryl couplings: Ligand selection: It is often crucial to optimize ligand selection by empirical screening of ligands and catalyst/ligand ratios: 4 P. Wipf 1/30/2007 For difficult substrates in the Suzuki coupling, it is useful to apply the following conditions: Review: Frisch, A. C.; Beller, M., "Catalysts for cross-coupling reactions with non-activated alkyl halides." Angew. Chem., Int. Ed. 2005, 44, 674-688. As the C(sp3)-X bond in alkyl halides is more electron rich than the C(sp2)-X bond in aryl and vinyl halides, the propensity of alkyl halides to undergo oxidative addition to a low-valent transition-metal complex (i.e.
    [Show full text]
  • Functionalized Nitrogen Ligands (CN) for Palladium Catalyzed Cross
    Journal of Organometallic Chemistry 881 (2019) 79e129 Contents lists available at ScienceDirect Journal of Organometallic Chemistry journal homepage: www.elsevier.com/locate/jorganchem Review Functionalized nitrogen ligands (CeN) for palladium catalyzed cross- coupling reactions (part II) Arjun Kumbhar Department of Chemistry, Padmabhushan Dr. Vasantraodada Patil College, Tasgaon, Affiliated to Shivaji University, Kolhapur, Maharashtra, 416312, India article info abstract Article history: In recent years, considerable effort has been focused in Pd catalyzed cross-coupling reactions, especially Received 6 April 2018 the use of less reactive and economically viable substrates like aryl chlorides. Unfortunately, Pd com- Received in revised form plexes containing the ligands having only N as a donor atom has some limitations, as it couples, mostly 22 September 2018 aryl iodides and bromides with different nucleophiles, and shows less activity towards aryl chlorides. Accepted 24 September 2018 This restriction can overwhelm by the use of Pd complexes containing N in combination with the C as a Available online 3 October 2018 donor atom such as palladacycles, pincers, PEPPSI and carbene ligands. The advantages of these ligands include high activity with enhanced selectivity, less toxicity, moisture, air as well as thermal stability. Keywords: Palladium Most importantly, such complexes have broad applications in catalysis under ambient conditions. This e Nitrogen ligands part of compressive review highlights the results of the highly active C N based Pd complexes and their NeC complexes applications in cross-coupling reactions. In the next part, we will cover all ligands and complexes con- Cross-couplings taining N in combination with P, O and S as a donor atoms (Pd catalysts based on CeP, CeO and CeS ligands).
    [Show full text]
  • Exploring Mechanisms in Ni Terpyridine Catalyzed C–C Cross-Coupling Reactions—A Review
    inorganics Review Exploring Mechanisms in Ni Terpyridine Catalyzed C–C Cross-Coupling Reactions—A Review Yulia H. Budnikova 1,2,* ID , David A. Vicic 3,* and Axel Klein 4,* ID 1 A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Center of Russian Academy of Sciences, 8, Arbuzov Str., 420088 Kazan, Russia 2 A. M. Butlerov Chemistry Institute, Kazan Federal University, Kremlevskaya str. 18, 420008 Kazan, Russia 3 Department of Chemistry, Lehigh University, 6 E. Packer Ave., Bethlehem, PA 18015, USA 4 Department für Chemie, Institut für Anorganische Chemie, Universität zu Köln, Greinstraße 6, D-50939 Köln, Germany * Correspondence: [email protected] (Y.H.B.); [email protected] (D.A.V.); [email protected] (A.K.); Tel.: +49-221-470-4006 (A.K.) Received: 9 November 2017; Accepted: 18 January 2018; Published: 23 January 2018 Abstract: In recent years, nickel has entered the stage for catalyzed C–C cross-coupling reactions, replacing expensive palladium, and in some cases enabling the use of new substrate classes. Polypyridine ligands have played an important role in this development, and the prototypical tridentate 2,20:60,200-terpyridine (tpy) stands as an excellent example of these ligands. This review summarizes research that has been devoted to exploring the mechanistic details in catalyzed C–C cross-coupling reactions using tpy-based nickel systems. Keywords: nickel; 2,20:60,200-terpyridine; catalysis; mechanism; electrosynthesis; cross-coupling 1. Introduction Polypyridine ligands such as 2,20-bipyridine (bpy) and 2,20:60,200-terpyridine (tpy) are common ligands in coordination chemistry and molecular catalysis, and they generally generate stable well-defined complexes [1–3].
    [Show full text]