DOCSLIB.ORG

Synthesis of Thiacrown and Azacrown Ethers Based on the Spiroacetal Framework

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Synthesis of Thiacrown and Azacrown Ethers Based on the Spiroacetal Framework By Marica Nikac A Thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy. University of Western Sydney February 2005. To my family and friends Acknowledgements I would like to express my enormous gratitude to my supervisors Dr. Robyn Crumbie, Prof. Margaret Brimble and Dr. Trevor Bailey for all their advice, support and encouragement throughout this project. I would also like to thank Assoc. Prof. Paul Woodgate and Dr. Vittorio “Cappy” Caprio for their suggestions. I would also like to thank the members of the Brimble group particularly Rosliana Halim, Michelle Lai, Christina Funnell, Jae Hyun Park and Kit Sophie Tsang for their encouragement and especially their friendship. I would not have made it without them. I would also like to thank Daniel Furkert and Adrian Blaser for their assistance and friendship. I would like to express my gratitude to Dr. Narsimha Reddy and Mike Walker for their help with everything to do with NMR. I also wish to thank the technical staff at the Universities of Auckland and Western Sydney particularly, Noel Renner, Chris Myclecharane and Gloria Tree. I would like to thank my family (especially my sister Milka) and friends for their support, encouragement and love throughout all these years. Finally I wish to thank all the students and staff at the Universities of Auckland and Western Sydney. Statement of Authentication The work presented in this thesis is, to the best of my knowledge and belief, original except as acknowledged in the text. I hereby declare that I have not submitted this material, either in whole or in part, for a degree at this or any other institution. …………………………………………. Table of Contents Page Table of Contents i List of Tables v List of Figures vi Abbreviations vii Abstract ix Chapter 1: Crown Ethers 1.0 Discovery of Crown Ethers 1 1.1 Crown Ethers Containing Carbohydrate Scaffolds 4 1.1.1 Crown Ethers Containing Pyranose Units 6 1.1.2 Lactose Trehalose and Other Di- and Trisaccharides 10 1.1.3 Furanoside Derivatives 12 1.2 Crown Ethers Containing the Spiroacetal Framework 13 1.2.1 Starands 13 1.2.2 Incorporation of the 1,4,7,10-Tetraoxaspiro[5.5]undecane Ring System 14 1.2.3 Polyspiroacetal Ligands 15 1.2.4 Incorporation of 1,7-Dioxaspiro[5.5]undecane Ring System 15 Chapter 2: Synthetic Strategies for the Preparation of Crown Ethers 2.0 General Synthetic Principles for the Preparation of Crown Ethers 20 2.0.1 The Effect of the Chain Length 20 2.0.2 Nature of the Atoms 21 2.0.3 Type Of Cyclisation 21 2.0.4 Ring Closure Methods 22 2.1 Selectivity of Crown Ethers for Metal Ions 23 2.2 Nitrogen Macrocycles (Azacrown Ethers) 26 i 2.2.1 Templated Syntheses 27 2.2.2 The Sulfonamide Method 29 2.2.3 Azacrown Ethers via Amide Formation 31 2.2.4 Peptide Chemistry 34 2.2.5 Crab-like Cyclisation 34 2.3 Sulfur Macrocycles (Thiacrown Ethers) 2.3.1 Synthesis of Thiacrown Compounds Using Cs2CO3 38 2.3.2 The Cesium Effect 38 2.3.3 Templated Syntheses 39 Chapter 3: Synthesis of Spiroacetal Thiacrown and Azacrown Ethers 3.0 Synthetic Targets 42 3.1 Synthesis of Spiroacetal Diol (50) 43 3.1.1 Synthesis of (±)-1,7-Dioxaspiro[5.5]undec-4-ene 43 3.1.2 Epoxidation of Olefin (114) 45 3.1.3 Base-Induced Ring opening of Epoxide (115) and Epoxidation of Allylic Alcohol (117) 46 3.1.4 Reduction of syn-Epoxy Alcohol (119) 48 3.2 Synthesis of the Spiroacetal Thiacrown Ethers via Path A 49 3.2.1 Synthesis of the β-Chloroethyl Sulfides (104), (127) and (128) 49 3.2.2 Reaction Between Spiroacetal Diol (50) and β-Chloroethyl Sulfide (104) 51 3.2.3 Attempted Synthesis of Thiacrown Ether (134) via Olefin 52 Metathesis of Diene (132) with Spiroacetal Diene (133) 52 3.2.3.1 Synthesis of Spiroacetal Bisallyl Ether (133) 53 3.2.3.2 Olefin Metathesis 54 3.4 Synthesis of the Spiroacetal thiacrown Ethers via Path B 61 3.4.1 Synthesis of Spiroacetal Diol (145) 62 3.4.2 Ditosylation of Spiroacetal Diol (145) 64 3.4.3 Synthesis of Spiroacetal Thiacrown Ethers (55), (56) and (57) 65 3.5 Synthesis of Spiroacetal Azacrown Ethers 68 3.5.1 Attempted Synthesis of Spiroacetal Azacrown Ethers (58), (59) And (60) via Imine Formation from Aldehyde (150) 69 ii 3.5.2 The Sulfonamide Method 70 3.6 Summary 74 Chapter 4: Spiroacetal Thiacrown Ethers As Primary and Secondary Ligands 4.0 Spiroacetal Thiacrown Ethers As Primary and Secondary Ligands 75 4.0.1 Crown Ethers As Primary Ligands 75 4.0.2 Second-Sphere Coordination 76 4.1 Binding Studies 78 4.1.1 Determination of Association Constants Using Picrate Salts 78 4.1.2 Interaction of Thiacrown Ethers (55), (56) and (57) with Neutral and Ionic Complexes (Second-Sphere Coordination) 82 4.1.2.1 Interaction With [Co(NH3)NO2](BPh4)2 (165) and [Co(en)3](BPh4)3 (166) 83 4.1.2.2 Interaction With [Al(acac)3] (164) 84 4.2 Summary 86 Chapter 5: Kinetic Resolution of the Spiroacetal Moiety 5.0 Kinetic Resolutions 87 5.1 Base-Induced Rearrangement Of Epoxides 88 5.1.1 Ring Opening of α-Epoxide (115) Using Chiral Non-Racemic Lithium Amide Bases 89 5.2 Hydrolytic Kinetic Resolution 91 5.2.1 Jacobsen Hydrolytic Resolution Reaction 91 5.2.2 Hydrolytic Kinetic Resolution of α-Epoxide (115) 92 5.3 Sharpless Epoxidation 94 5.3.1 Sharpless Epoxidation of Allylic Alcohol (117) 96 5.4 Summary 98 iii Chapter 6: Conclusion Conclusion 100 Chapter 7: Experimental 7.0 General Details 105 7.1 Preparation of [3R∗, 5S∗, 6S∗]-1,7-Dioxaspiro[5.5]undecan-3,5-diol (50) 106 7.2 Synthesis of [3R∗, 5S∗, 6S∗]-1,7-Dioxaspiro[5.5]undecan-3,5-diyl bis(ethyl p-toluenesulfonate) (146) 115 7.3 Preparation of β-Chloroethyl Sulfides (104) and (127) and Dithiols (122) and (123) 120 7.4 Synthesis of Spiroacetal Thiacrown Ethers (55), (56) and (57) 125 7.5 Synthesis of Spiroacetal Azacrown Ether (58) 128 7.6 Olefin Metathesis of Spiroacetal Bisallyl Ether (142) 132 7.7 Kinetic Resolution Reactions 134 7.8 Second-Sphere Complexation 142 Chapter 8: References References 143 iv List of Tables Page Table 1: Selected 1H Chemical Shifts and Coupling For Dimers (142a), (142b) and (142c) 60 Table 2: Reaction Conditions Used in the Synthesis of Diester (149) 62 Table 3: Reaction Conditions Used in the Synthesis of Protected Azacrown (159) 72 Table 4: Association Constants For Spiroacetal Thiacrown Ethers (55), (56) and (57) 79 Table 5: Base-Induced Rearrangement of α-Epoxide (115) Using Chiral Lithium Amide Bases 90 v List of Figures Page Figure 1: Association Constants of the Axial Crown Ethers 16 Figure 2: Association Constants of the Equatorial Crown Ethers 17 Figure 3: Resolution of Spiroacetal Diol (50) 19 Figure 4: Common Approaches to Synthesising Macrocycles 20 Figure 5: Sandwich Effect 24 Figure 6: Common Structure of Complexed Azacrown Ethers 25 Figure 7: Effect of the Longer Carbon-Sulfur Bond on the Cavity of Thiacrown Compounds 26 Figure 8: Cesium Effect 39 Figure 9: Hydrogen Bonding in the Epoxidation of Allylic Alcohol (117) using meta -chloroperoxybenzoic acid 48 Figure 10: Proton Driven Transport of Metal Ions Through Membranes 76 Figure 11: Second-Sphere Coordination 77 Figure 12: Second-Sphere Coordination of Carboplatin 77 Figure 13: Association Constants of the Thiacrown Ethers (55), (56) and (57) 80 Figure 14: Expanded Region 80 Figure 15: Holodirected and Hemidirected Geometry of Pb(II) 82 Figure 16: Electrostatic Potential Map of [Al(acac)3] 85 Figure 17: Electrostatic Potential Map of Thiacrown (55) 85 Figure 18: Differentiation Between Two syn β-Protons in Cyclohexene Oxide 88 Figure 19: Mechanism of the Sharpless Epoxidation 95 Figure 20: Kinetic Resolution of Stereochemically Rigid Compounds Using Sharpless Epoxidation 96 Figure 21: Determination of the Appropriate Tartrate in the Epoxidation of Allylic Alocohol (117) 97 vi Abbreviations 2D. two dimensional 18-Crown-6 1,4,7,10,13,16-hexaoxacyclooctadecane 18-S-6 1,4.7,10,13,16-hexathiacyclooctadecane 9-S-3 1,4,7-trithiacyclononane Ar. Aryl aq. aqueous ax. axial n-Bu, Bun. n-butyl t-Bu, But. tert-butyl CI. chemical ionisation (mass spectroscopy) cm3. cubic centimetres conc. concentration COSY. correlation spectroscopy D. deuterium deg. degrees DEPT. distortionless enhancement by polarisation transfer dil. dilute DMDO. dimethyldioxirane DMAP. 4-dimethylaminopyridine DMF. N,N-dimethylformamide DMSO. dimethylsulfoxide ee. enantiomeric excess EI. electron impact ionisation (mass spectroscopy) eq. equatorial equiv. equivalent Et. ethyl h. hour HMQC. Heteronuclear Multiple Quantum Correlation HMBC. Heteronuclear Multiple Bond Correlation HSQC. Heteronuclear Single Quantum Correlation vii IR. infrared spectroscopy J. NMR coupling constant Ka. association constant L. ligand m-CPBA. meta-chloroperoxybenzoicacid Me. methyl min. minute mmol. millimoles mol. moles mp. melting point NMR. nuclear magnetic resonance Ns. nosyl, o-nitrobenzenesulfonyl Oxone® potassium peroxymonosulfate IPr. isopropyl PPTS. pyridinium p-toluenesulfonate THF. tetrahydrofuran TMS. trimethylsilyl Ts. tosyl, p-toluenesulfonyl viii Abstract This thesis describes the synthesis of novel thiacrown and azacrown ethers based on the 1,7-dioxaspiro[5.5]undecane ring system. Chapter one presents an overview of the discovery and development of crown ethers. The incorporation of naturally occurring compounds into the crown ether framework such as carbohydrates and more recently the spiroacetal functionality is also described. Chapter two describes the synthetic strategies available for the synthesis of crown ethers, azacrown ethers and thiacrown ethers.
Recommended publications
  • Philosophy of Science and Philosophy of Chemistry

    Philosophy of Science and Philosophy of Chemistry

    Philosophy of Science and Philosophy of Chemistry Jaap van Brakel Abstract: In this paper I assess the relation between philosophy of chemistry and (general) philosophy of science, focusing on those themes in the philoso- phy of chemistry that may bring about major revisions or extensions of cur- rent philosophy of science. Three themes can claim to make a unique contri- bution to philosophy of science: first, the variety of materials in the (natural and artificial) world; second, extending the world by making new stuff; and, third, specific features of the relations between chemistry and physics. Keywords : philosophy of science, philosophy of chemistry, interdiscourse relations, making stuff, variety of substances . 1. Introduction Chemistry is unique and distinguishes itself from all other sciences, with respect to three broad issues: • A (variety of) stuff perspective, requiring conceptual analysis of the notion of stuff or material (Sections 4 and 5). • A making stuff perspective: the transformation of stuff by chemical reaction or phase transition (Section 6). • The pivotal role of the relations between chemistry and physics in connection with the question how everything fits together (Section 7). All themes in the philosophy of chemistry can be classified in one of these three clusters or make contributions to general philosophy of science that, as yet , are not particularly different from similar contributions from other sci- ences (Section 3). I do not exclude the possibility of there being more than three clusters of philosophical issues unique to philosophy of chemistry, but I am not aware of any as yet. Moreover, highlighting the issues discussed in Sections 5-7 does not mean that issues reviewed in Section 3 are less im- portant in revising the philosophy of science.
  • Organic Synthesis: Handout 1

    Organic Synthesis: Handout 1

    Prof Tim Donohoe: Strategies and Taccs in Organic Synthesis: Handout 1 Organic Synthesis III 8 x 1hr Lectures: Michaelmas Term Weeks 5-8 2016 Mon at 10am; Wed at 9am Dyson Perrins lecture theatre Copies of this handout will be available at hEp://donohoe.chem.ox.ac.uk/page16/index.html 1/33 Prof Tim Donohoe: Strategies and Taccs in Organic Synthesis: Handout 1 Organic Synthesis III Synopsis 1) Introduc5on to synthesis: (i) Why do we want to synthesise molecules- what sort of molecules do we need to make? (ii) What aspects of selecvity do we need to accomplish a good synthesis (chemo-, regio- and stereoselecvity)? (iii) Protecng group chemistry is central to any syntheAc effort (examples and principles) (iv) What is the perfect synthesis (performed in industry versus academia)? 2) The chiral pool: where does absolute stereochemistry come from? 3) Retrosynthesis- learning to think backwards (revision from first and second year). Importance of making C-C bonds and controlling oxidaAon state. Umpolung 4) Some problems to think about 5) Examples of retrosynthesis/synthesis in ac5on. 6) Ten handy hints for retrosynthesis 7) Soluons to the problems Recommended books: General: Organic Chemistry (Warren et al) Organic Synthesis: The DisconnecRon Approach (S. Warren) Classics in Total Synthesis Volumes I and II (K. C. Nicolaou) The Logic of Chemical Synthesis (E. J. Corey) 2/33 View Article Online / Journal Homepage / Table of Contents for this issue 619461 Strychniqae and BYucine. Pavt XLII. 903 Prof Tim Donohoe: Strategies and Taccs in Organic Synthesis: Handout 1 (i) Why do we want to synthesise complex molecules? Isolated from the Pacific Yew in 1962 Prescribed for prostate, breast and ovarian cancer Unique mode of acRon 1x 100 year old tree = 300 mg Taxol Isolated in 1818- poisonous Stuctural elucidaon took R.
  • Enantioselective Total Synthesis of (-)-Deoxoapodine

    Enantioselective Total Synthesis of (-)-Deoxoapodine

    Enantioselective total synthesis of (-)-deoxoapodine The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Kang, Taek, et al., "Enantioselective total synthesis of (-)- deoxoapodine." Angewandte Chemie International Edition 56, 44 (Sept. 2017): p. 13857-60 doi 10.1002/anie.201708088 ©2017 Author(s) As Published 10.1002/anie.201708088 Publisher Wiley Version Author's final manuscript Citable link https://hdl.handle.net/1721.1/125957 Terms of Use Creative Commons Attribution-Noncommercial-Share Alike Detailed Terms http://creativecommons.org/licenses/by-nc-sa/4.0/ HHS Public Access Author manuscript Author ManuscriptAuthor Manuscript Author Angew Manuscript Author Chem Int Ed Engl Manuscript Author . Author manuscript; available in PMC 2018 October 23. Published in final edited form as: Angew Chem Int Ed Engl. 2017 October 23; 56(44): 13857–13860. doi:10.1002/anie.201708088. Enantioselective Total Synthesis of (−)-Deoxoapodine Dr. Taek Kang§,a, Dr. Kolby L. White§,a, Tyler J. Mannb, Prof. Dr. Amir H. Hoveydab, and Prof. Dr. Mohammad Movassaghia aDepartment of Chemistry, Massachusetts Institute of Technology Cambridge, MA 02139 (USA) bDepartment of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467 (USA) Abstract The first enantioselective total synthesis of (−)-deoxoapodine is described. Our synthesis of this hexacyclic aspidosperma alkaloid includes an efficient molybdenum-catalyzed enantioselective ring-closing metathesis reaction for desymmetrization of an advanced intermediate that introduces the C5-quaternary stereocenter. After C21-oxygenation, the pentacyclic core was accessed via an electrophilic C19-amide activation and transannular spirocyclization. A biogenetically inspired dehydrative C6-etherification reaction proved highly effective to secure the F-ring and the fourth contiguous stereocenter of (−)-deoxoapodine with complete stereochemical control.
  • The Total Synthesis of Securinine and Other Methodology Studies

    The Total Synthesis of Securinine and Other Methodology Studies

    University of Windsor Scholarship at UWindsor Electronic Theses and Dissertations Theses, Dissertations, and Major Papers 2010 The total synthesis of securinine and other methodology studies Bhartesh Dhudshia University of Windsor Follow this and additional works at: https://scholar.uwindsor.ca/etd Recommended Citation Dhudshia, Bhartesh, "The total synthesis of securinine and other methodology studies" (2010). Electronic Theses and Dissertations. 8275. https://scholar.uwindsor.ca/etd/8275 This online database contains the full-text of PhD dissertations and Masters’ theses of University of Windsor students from 1954 forward. These documents are made available for personal study and research purposes only, in accordance with the Canadian Copyright Act and the Creative Commons license—CC BY-NC-ND (Attribution, Non-Commercial, No Derivative Works). Under this license, works must always be attributed to the copyright holder (original author), cannot be used for any commercial purposes, and may not be altered. Any other use would require the permission of the copyright holder. Students may inquire about withdrawing their dissertation and/or thesis from this database. For additional inquiries, please contact the repository administrator via email ([email protected]) or by telephone at 519-253-3000ext. 3208. The Total Synthesis of Securinine and Other Methodology Studies by Bhartesh Dhudshia A Dissertation Submitted to the Faculty of Graduate Studies through the Department of Chemistry and Biochemistry in Partial Fulfillment of the Requirements
  • Peptide Chemistry up to Its Present State

    Peptide Chemistry up to Its Present State

    Appendix In this Appendix biographical sketches are compiled of many scientists who have made notable contributions to the development of peptide chemistry up to its present state. We have tried to consider names mainly connected with important events during the earlier periods of peptide history, but could not include all authors mentioned in the text of this book. This is particularly true for the more recent decades when the number of peptide chemists and biologists increased to such an extent that their enumeration would have gone beyond the scope of this Appendix. 250 Appendix Plate 8. Emil Abderhalden (1877-1950), Photo Plate 9. S. Akabori Leopoldina, Halle J Plate 10. Ernst Bayer Plate 11. Karel Blaha (1926-1988) Appendix 251 Plate 12. Max Brenner Plate 13. Hans Brockmann (1903-1988) Plate 14. Victor Bruckner (1900- 1980) Plate 15. Pehr V. Edman (1916- 1977) 252 Appendix Plate 16. Lyman C. Craig (1906-1974) Plate 17. Vittorio Erspamer Plate 18. Joseph S. Fruton, Biochemist and Historian Appendix 253 Plate 19. Rolf Geiger (1923-1988) Plate 20. Wolfgang Konig Plate 21. Dorothy Hodgkins Plate. 22. Franz Hofmeister (1850-1922), (Fischer, biograph. Lexikon) 254 Appendix Plate 23. The picture shows the late Professor 1.E. Jorpes (r.j and Professor V. Mutt during their favorite pastime in the archipelago on the Baltic near Stockholm Plate 24. Ephraim Katchalski (Katzir) Plate 25. Abraham Patchornik Appendix 255 Plate 26. P.G. Katsoyannis Plate 27. George W. Kenner (1922-1978) Plate 28. Edger Lederer (1908- 1988) Plate 29. Hennann Leuchs (1879-1945) 256 Appendix Plate 30. Choh Hao Li (1913-1987) Plate 31.
  • Potassium-Selective PVC Membrane Electrodes Based on Newly Synthesized Cis- and Trans-Bis(Crown Ether)S

    Potassium-Selective PVC Membrane Electrodes Based on Newly Synthesized Cis- and Trans-Bis(Crown Ether)S

    ANALYTICAL SCIENCES OCTOBER 1998, VOL. 14 1009 1998 © The Japan Society for Analytical Chemistry Notes Potassium-Selective PVC Membrane Electrodes Based on Newly Synthesized cis- and trans-Bis(crown ether)s Kum-Chul OH*, Eun Chul KANG*, Young Lag CHO**, Kyu-Sung JEONG**, Eun-Ah YOO*** and Ki-Jung PAENG*† *Department of Chemistry, Yonsei University, Wonju, 220-710, Korea **Department of Chemistry, Yonsei University, Seoul, 120-749, Korea ***Department of Chemistry, Sungshin Women’s University, Seoul, 136-742, Korea Keywords Potassium-selective PVC membrane electrodes, bis(benzocrown ether)s, geometric isomer Ion-selective electrodes (ISEs) based on ionophore- al.10 and Moriaty et al.13 reported that the rigid and impregnated polymer membranes for potassium ion compact hydrocarbons such as xanthene or cubane are (K+) are steadily replacing flame photometry and other more relevant for this purpose than commercially assay techniques for monitoring K+ in various matrices available long-chain hydrocarbons (Fluka potassium and have been widely used in numerous analytical ionophore II; Fig. 1) that may increase lipophilicity but applications.1 These ISEs incorporate neutral also decrease the mobility of the carrier. ionophores such as valinomycin (Fluka potassium Recently we reported the newly synthesized geomet- ionophore I, Fig. 1)2–4, crown ether5–10 and recently rical isomer of cis- and trans-bis(benzocrown ether)s rifamycin11 as active membrane components. Among (Fig. 1) which are derived from a new structurally well- the reported ionophores, valinomycin is by far, the most successful ionophore for K+ ion. However, valino- mycin is a very expensive reagent with toxicity, and its membrane can be pertially blocked by coexisting Cs+, + + + Rb and possibly NH4 in the determination of K .
  • Recent Advances in Total Synthesis Via Metathesis Reactions

    Recent Advances in Total Synthesis Via Metathesis Reactions

    SYNTHESIS0039-78811437-210X © Georg Thieme Verlag Stuttgart · New York 2018, 50, 3749–3786 review 3749 en Syn thesis I. Cheng-Sánchez, F. Sarabia Review Recent Advances in Total Synthesis via Metathesis Reactions Iván Cheng-Sánchez Francisco Sarabia* Department of Organic Chemistry, Faculty of Sciences, University of Málaga, Campus de Teatinos s/n. 29071- Málaga, Spain [email protected] Received: 16.04.2018 ly explained by the emergence, design, and development of Accepted after revision: 30.05.2018 powerful catalysts that are capable of promoting striking Published online: 18.07.2018 DOI: 10.1055/s-0037-1610206; Art ID: ss-2018-z0262-r transformations in highly efficient and selective fashions. In fact, the ability of many of them to forge C–C bonds be- Abstract The metathesis reactions, in their various versions, have be- tween or within highly functionalized and sensitive com- come a powerful and extremely valuable tool for the formation of car- pounds has allowed for the preparation of complex frame- bon–carbon bonds in organic synthesis. The plethora of available cata- lysts to perform these reactions, combined with the various works, whose access were previously hampered by the lim- transformations that can be accomplished, have positioned the me- itations of conventional synthetic methods. Among the tathesis processes as one of the most important reactions of this centu- myriad of recent catalysts, those developed and designed to ry. In this review, we highlight the most relevant synthetic contributions promote metathesis reactions have had a profound impact published between 2012 and early 2018 in the field of total synthesis, reflecting the state of the art of this chemistry and demonstrating the and created a real revolution in the field of total synthesis, significant synthetic potential of these methodologies.
  • Total Synthesis of ( )-Hennoxazole a Vol

    Total Synthesis of ( )-Hennoxazole a Vol

    ORGANIC LETTERS − 2007 Total Synthesis of ( )-Hennoxazole A Vol. 9, No. 6 1153-1155 Thomas E. Smith,* Wen-Hsin Kuo, Victoria D. Bock, Jennifer L. Roizen, Emily P. Balskus, and Ashleigh B. Theberge Department of Chemistry, Williams College, Williamstown, Massachusetts 01267 [email protected] Received January 31, 2007 ABSTRACT An enantioselective, convergent, total synthesis of the antiviral marine natural product (−)-hennoxazole A has been completed in 17 steps, longest linear sequence, from serine methyl ester and in 9 steps from an achiral bisoxazole intermediate. Elaboration of a thiazolidinethione allowed for rapid assembly of the pyran-based ring system. Key late-stage coupling was effected by deprotonation of the bisoxazole methyl group, followed by alkylation with an allylic bromide side chain segment. Marine natural products have become increasingly important Williams,5 and Shioiri6 laboratories.7 In this communication, as lead compounds for the development of new drugs as a we report the shortest asymmetric total synthesis of hen- consequence of their intriguing structural diversity and noxazole A to date. biological activity.1 Hennoxazole A (1), first isolated by The development of relatively mild conditions for the Scheuer from the marine sponge Polyfibrospongia, displays preparation of oxazoles has made the late-stage assembly of antiviral activity against herpes simplex type 1, as well as these ring systems a common, albeit not always efficient, peripheral analgesic behavior.2 The two contiguous 2,4- strategy in the synthesis
  • Crown Ethers and Their Alkali Metal Ion Complexes As Assembler Groups in Uranyl–Organic Coordination Polymers With

    Crown Ethers and Their Alkali Metal Ion Complexes As Assembler Groups in Uranyl–Organic Coordination Polymers With

    Crown Ethers and Their Alkali Metal Ion Complexes as Assembler Groups in Uranyl–Organic Coordination Polymers with cis -1,3-, cis -1,2-, and trans -1,2-Cyclohexanedicarboxylates Pierre Thuéry, Youssef Atoini, Jack Harrowfield To cite this version: Pierre Thuéry, Youssef Atoini, Jack Harrowfield. Crown Ethers and Their Alkali Metal Ion Complexes as Assembler Groups in Uranyl–Organic Coordination Polymers with cis -1,3-, cis -1,2-, and trans - 1,2-Cyclohexanedicarboxylates. Crystal Growth & Design, American Chemical Society, In press, 18 (5), pp.3167-3177. 10.1021/acs.cgd.8b00266. cea-01759418 HAL Id: cea-01759418 https://hal-cea.archives-ouvertes.fr/cea-01759418 Submitted on 6 Apr 2018 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. Crown Ethers and their Alkali Metal Ion Complexes as Assembler Groups in Uranyl–Organic Coordination Polymers with cis -1,3-, cis -1,2- and trans -1,2-Cyclohexanedicarboxylates Pierre Thuéry* ,† Youssef Atoini ‡ and Jack Harrowfield*,‡ †NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France ‡ISIS, Université de Strasbourg, 8 allée Gaspard Monge, 67083 Strasbourg, France ABSTRACT: Alkali metal cations (Na +, K +) and crown ether molecules (12C4, 15C5, 18C6) were used as additional reactants during the hydrothermal synthesis of uranyl ion complexes with cis /trans -1,3-, cis -1,2- and trans -1,2- cyclohexanedicarboxylic acids ( c/t-1,3-chdcH2, c-1,2-chdcH2 and t-1,2-chdcH2, respectively, the latter as racemic or pure (1 R,2 R) enantiomer).
  • Schiff's Bases and Crown Ethers As Supramolecular Sensing Materials in the Construction of Potentiometric Membrane Sensors

    Schiff's Bases and Crown Ethers As Supramolecular Sensing Materials in the Construction of Potentiometric Membrane Sensors

    Sensors 2008, 8, 1645-1703 sensors ISSN 1424-8220 © 2008 by MDPI www.mdpi.org/sensors Review Schiff's Bases and Crown Ethers as Supramolecular Sensing Materials in the Construction of Potentiometric Membrane Sensors Farnoush Faridbod 1, Mohammad Reza Ganjali 1,*, Rassoul Dinarvand 2, Parviz Norouzi 1 and Siavash Riahi 3 1 Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran 2 Medical Nanotechnology Research Centre, Medical Sciences/University of Tehran, Tehran, P.O. Box 14155-6451, Iran 3 Institute of Petroleum Engineering, Faculty of Engineering, University of Tehran, Tehran, P.O. Box 14155-6455, Iran * Author to whom correspondence should be addressed; E-mail: [email protected] Received: 31 December 2007 / Accepted: 22 February 2008 / Published: 11 March 2008 Abstract: Ionophore incorporated PVC membrane sensors are well-established analytical tools routinely used for the selective and direct measurement of a wide variety of different ions in complex biological and environmental samples. Potentiometric sensors have some outstanding advantages including simple design and operation, wide linear dynamic range, relatively fast response and rational selectivity. The vital component of such plasticized PVC members is the ionophore involved, defining the selectivity of the electrodes' complex formation. Molecular recognition causes the formation of many different supramolecules. Different types of supramolecules, like calixarenes, cyclodextrins and podands, have been used as a sensing material in the construction of ion selective sensors. Schiff's bases and crown ethers, which feature prominently in supramolecular chemistry, can be used as sensing materials in the construction of potentiometric ion selective electrodes. Up to now, more than 200 potentiometric membrane sensors for cations and anions based on Schiff's bases and crown ethers have been reported.
  • Synthesis of New Aza- and Thia-Crown Ethers and Their Metal Ion Templates Synthesis As Model Case Study

    Synthesis of New Aza- and Thia-Crown Ethers and Their Metal Ion Templates Synthesis As Model Case Study

    General Papers ARKIVOC 2014 (iv) 242-251 Synthesis of new aza- and thia-crown ethers and their metal ion templates synthesis as model case study Mahmood Kamali, Abbas Shockravi,* Reza Mohtasham, and Somayeh Pahlavan Moghanlo Faculty of Chemistry, Kharazmi University, Mofatteh Ave., No.49, 15614 Tehran, Iran E-mail: [email protected] , [email protected] DOI: http://dx.doi.org/10.3998/ark.5550190.0015.400 Abstract Four new thia- and four new aza- crown ethers were synthesized using the reaction of ethylene glycols ditosylated with 1,1´-(2,2´-dihydroxynaphthyl)sulfide ( DNS ) and 2,6-bis(3- hydroxyphenyl)-4-phenylpyridine in acetonitrile as solvent in the presence of bases (LiOH, NaOH, KOH and Cs 2CO 3). In the synthesis of macrocycles based on DNS , the template effects of alkaline metal ions; Li +, Na +, K + and Cs + on the reaction yields were investigated. Sodium template generally was more effective for the synthesis of all four macrocycles. Relatively, good yields of 15- and 18-membered macrocycles were obtained in the presence of all kinds of applied cations. K+ Cation was more effective template ion than Na + in the formation of 18-membered macrocycles due to their larger cavity size compared to the 15-membered cycles. The structures of macrocycles were confirmed by CHN/O analysis, IR, 1H NMR, 13 C NMR and mass spectrometry. Keywords: Aza-crown ether, thia-crown ether, template effect, dinaphthylsulfide, 2,4,6- triarylpyridine, naphthalene, pyridine Introduction Crown ethers were the first synthetic structures contributing to the vastly increasing field of Host-Guest and molecular recognition chemistry.
  • Uranyl-(12-Crown-4) Ether Complexes and Derivatives: Structural Characterization and Isomeric Differentiation

    Uranyl-(12-Crown-4) Ether Complexes and Derivatives: Structural Characterization and Isomeric Differentiation

    Uranyl-(12-Crown-4) Ether Complexes and Derivatives: Structural Characterization and Isomeric Differentiation Jiwen Jian, a,† Shu-Xian Hu,b,c,† Wan-Lu Li,c Michael J. van Stipdonk,d Jonathan Martens,e Giel Berden,e Jos Oomens,e,f Jun Li c,*, John K. Gibsona,* aChemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA b Beijing Computational Science Research Center, Beijing 100193, China c Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China dDepartment of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282 USA eRadboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands fvan‘t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands †These authors contributed equally to this work. *Corresponding authors email addresses: [email protected] (Li); [email protected] (Gibson) 1 Abstract The following gas-phase uranyl/12-Crown-4 (12C4) complexes were synthesized by electrospray 2+ + ionization: [UO2(12C4)2] and [UO2(12C4)2(OH)] . Collision induced dissociation (CID) of the + dication resulted in [UO2(12C4-H)] (12C4-H is a 12C4 that has lost one H), which + spontaneously adds water to yield [UO2(12C4-H)(H2O)] . The latter has the same composition + + as [UO2(12C4)(OH)] produced by CID of [UO2(12C4)2(OH)] but exhibits different reactivity + + with water. The postulated structures as isomeric [UO2(12C4-H)(H2O)] and [UO2(12C4)(OH)] were confirmed by comparison of infrared multiphoton dissociation (IRMPD) spectra with + computed spectra. The structure of [UO2(12C4-H)] corresponds to cleavage of a C-O bond in the 12C4 ring, with formation of a discrete U-Oeq bond and equatorial coordination by three intact ether moieties.