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Investigations Into Ligand Substitutions of Rhenium

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Investigations Into Ligand Substitutions of Rhenium INVESTIGATIONS INTO LIGAND SUBSTITUTIONS OF RHENIUM AND MOLYBDENUM d4 HEXANUCLEAR CLUSTERS AND THE SYNTHESIS AND CHARACTERIZATION OF AURATED PYRENE AND THIOPHENE DERIVATIVES By MIYA ALETHEA PEAY Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Thesis Adviser: Dr. Thomas Gray Department of Chemistry CASE WESTERN RESERVE UNIVERSITY August, 2011 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of _____Miya Peay________________________________________ candidate for the ______Doctorate of Philosophy _____degree *. (signed)_____John Protasiewicz____________________________ (chair of the committee) ___________ Irene Lee ____________________________ ___________ John Stuehr __________________________ __ Anthony Berdis __ _____________________ ___ Thomas Gray__________________________ ________________________________________________ (date) ___August 2011__________ *We also certify that written approval has been obtained for any proprietary material contained therein. Dedicated To: God the Father, the Son, and the Holy Spirit, the One who strengthens me and keeps me, To my family and friends for their undying love and support throughout the many years. I could not have done any of this without any of you! Finally to my unborn baby girl, Mommy has loved you from the day I found out about you. You mean more to me than I could have ever imagined and I can’t wait to show this to you in hopes that one day you’ll see it as a means to push yourself to greater heights as well. Table of Contents List of Tables……………………………………………………………………………..iii List of Figures……………………………………………………………………………iv List of Schemes…………………………………………………………………………viii Acknowledgements……………………………………………………………………….ix Abstract……………………………………………………………………………………x Chapter 1. General Introduction…………………………………………………………..1 Chapter 2. Ligand Substitution on Hexanuclear Rhenium(III) and Molybdenum(II) Clusters 2.1 Introduction………………………………………………………………….15 2.2 Results and Discussion………………………………………………………20 2.3 Conclusion…………………………………………………………………...26 2.4 Experimental…………………………………………………………………27 2.5 Cited Work…………………………………………………………………...43 Chapter 3. Synthesis and Characterization of Mono- and Diaurated Pyrenes 3.1 Introduction…………………………………………………………………..46 3.2 Results and Discussion………………………………………………………52 3.3 Conclusion…………………………………………………………………...62 3.4 Experimental…………………………………………………………………63 3.5 Cited Work…………………………………………………………………...73 Chapter 4. Synthesis and Crystal Structure of a Centrosymmetric, Di-Gold(I) Disubstituted Bithiophene 4.1 Introduction………………………………………………………………….77 i 4.2 Results and Discussion………………………………………………………83 4.3 Conclusion…………………………………………………………………...87 4.4 Experimental…………………………………………………………………88 4.5 Cited Work…………………………………………………………………...93 Chapter 5. Conclusion……………………………………………………………………97 Appendix. X-Ray Crystal Structure Data…..……………………………………………99 Bibliography……………………………………………………………………………179 ii List of Tables Chapter 2. 31 2.1: P NMR Chemical Shifts Relative to 85% H3PO4 (aq) of Phosphine-Ligated Clusters…………………………………………………………………………………..22 2.2: Crystallographic Data for Compound 2.13 Collected at 100 ± 2 K………………...25 2.3: Selected Interatomic Distances (Å) and Angles (deg) for 2.13……………………..25 Chapter 3. 31 3.1: P NMR Chemical Shifts Relative to 85% H3PO4 (aq) of Phosphine-Ligated Gold Complexes………………………………………………………………………………..54 3.2: Crystallographic Data for Compounds 3.7 and 3.8 Collected at 100 ± 2 K………...61 3.3: Selected Interatomic Distances (Å) and Angles (deg) for 3.7 and 3.8……………...61 Chapter 4. 4.1: Crystallographic Data for Compound 4.7 Collected at 100 ± 2 K………………….86 4.2: Selected Interatomic Distances (Å) and Angles (deg) for 4.7………………………86 iii List of Figures Chapter 1. 2– 1.1: Structure of [Mo6Cl14] , a representative cluster. Mo: violet, Cl, green……………1 1.2: Potential energy diagram for reactants (R), products in ground- and excited states (P and P* respectively), and electron-transfer free energies for ground- and excited states o o (ΔGr and ΔGex respectively)……………………………………………………………..3 1.3: General reaction cycle Suzuki coupling……………………………………………...5 1.4: The relativistic (R) and nonrelativistic (NR) orbital energies of AgH and AuH. Data are taken from Desclaux and Pyykkö……………………………………………………..7 1.5: Relativistic (<r>R) to nonrelativistic (<r>NR) ratio of the 6s-shell radii in the atomic ground states for elements 55-100. Data adapted from Pyykkö and Desclaux…………...7 1.6: Unsubstituted pyrene molecule……………………………………………………….8 1.7: IUPAC naming system for naming (a) thiophene, (b)-(d) isomeric bithiophenes, and (e) 3’-substituted terthiophene…………………………………………………………….9 Chapter 2. 2– 2.1: Structure of [Mo6Cl14] , a representative cluster. Mo: violet, Cl, green…………..15 2.2: Measurement of cone angle θ……………………………………………………….19 2.3: Cluster reaction and substitution position…………………………………………...21 2.4: Crystal structure of the anion of (Ph4P)2[Mo6Cl8(O3SCF3)6] (50%, 100 K). Legend: Mo, gray; Cl, light green, O, red; S, yellow, C, blue; F, lime green……………………..24 31 2.5: P NMR of trans-Re6Se8(PBu3)4I2…………………………………………………30 1 2.6: H NMR of trans-Re6Se8(PBu3)4I2.............................................................................31 31 2.7: P NMR of cis-Re6Se8(PBu3)4I2................................................................................32 iv 1 2.8: H cis-Re6Se8(PBu3)4I2...............................................................................................33 31 2.9: P [Re6Se8(PBu3)5I]I..................................................................................................34 1 2.10: H [Re6Se8(PBu3)5I]I.................................................................................................35 31 2.11: P NMR of trans-Re6S8(PBu3)4Br2………………………………………………..36 31 2.12: P NMR of cis-Re6S8(PBu3)4Br2………………………………………………….37 31 2.13: P NMR of [Re6S8(PBu3)5Br]Br…………………………………………………..38 2.14: MALDI Mass Spectra of trans-Re6Se8(PBu3)4I2…………………………………..39 2.15: MALDI- Mass Spectra cis-Re6Se8(PBu3)4I2.............................................................40 2.16: Mass Spectra of trans-Re6S8(PBu3)4Br2…………………………………………...41 2.17: Mass Spectra of cis-Re6S8(PBu3)4Br2……………………………………………...42 Chapter 3. 3.1: First and second generation gold-containing rheumatoid arthritis drugs. (1) Aurothioglucose, (2) disodium aurothiomalate, (3) tri-sodium bis(thiosulphato)gold, (4) aurothiopropanol sulphonate, (5) gold (I) 4-amino-2-mercaptobenzoate, and (6)[tetra-O- acetyl-β-D-(glucopyranosyl)thio]-triethyl-phosphine)gold(I)…………………………...47 3.2: Detailed pictorial view of a phosphinegold(I) aromatic complex…………………..51 3.3: Absorption spectra of 2-[(PCy3)Au]pyrene and 2,7-[(PCy3)Au]2pyrene in CH2Cl2..55 3.4: Absorption and emission of 2-[(PCy3)Au]pyrene in CHCl3………………………...56 3.5: Absorption and emission of 2,7-[(PCy3)Au]2pyrene in CHCl3……………………..57 3.6: Emission spectrum of digold(I) pyrene in a 2-methyltetrahydrofuran glass at 77 K.58 3.7: 2-[(PCy3)Au]pyrene (50%, 100 K). Hydrogen atoms are omitted for clarity. Unlabeled atoms are carbon……………………………………………………………...59 v 3.8: 2,7-[(PCy3)Au]2pyrene. 50% probability ellipsoids are shown. Hydrogen atoms and solvent molecules are omitted for clarity. Unlabeled atoms are carbon…………………60 31 3.9: P NMR 2-[(PCy3)Au]pyrene………………………………………………………66 1 3.10: H NMR 2-[(PCy3)Au]pyrene..................................................................................67 31 3.11: P NMR 2,7-[(PCy3)Au]2pyrene………………………………………………….68 1 3.12: H NMR 2,7-[(PCy3)Au]2pyrene..............................................................................69 31 3.13: P NMR 2,7-[(PPh3)Au]2pyrene..............................................................................70 1 3.14: H NMR 2,7-[(PPh3)Au]2pyrene...............................................................................71 3.15: Mass Spectra of 2,7-[(PCy3)Au]2pyrene…………………………………………...72 Chapter 4. 4.1: Resonance structures of polyenes, oligothiophenes, and oligo-p-phenylenes………78 4.2: Examples of various oligothiophenes used or synthesized for use in electronic applications………………………………………………………………………………80 4.3: First and second generation gold-containing rheumatoid arthritis drugs. (1) Aurothioglucose, (2) disodium aurothiomalate, (3) tri-sodium bis(thiosulphato)gold, (4) aurothiopropanol sulphonate, (5) gold (I) 4-amino-2-mercaptobenzoate, and (6)[tetra-O- acetyl-β-D-(glucopyranosyl)thio]-triethyl-phosphine)gold(I)…………………………...81 4.4: (a) 3,3’-Bis(diphenylphosphino)-2,2’-bithiophene gold(I) chloride and (b) 3,3’’’- Dihexyl-3’,3’’-bis(diphenylphosphino)-2,5’:2’,2’’:5’’,2’’’-quaterthiophene gold(I) chloride…………………………………………………………………………………..82 4.5: Absorbance spectra of 5,5’-[(PPh3)Au]2-2,2’-bithiophene and 5,5’-(Bpin)2-2,2’- bithiophene in CH2Cl2……………………………………………………………………84 vi 4.6: 5,5’-[(PPh3)Au]2-2,2’-bithiophene. 50% probability ellipsoids are shown. Hydrogen atoms and solvent molecules are omitted for clarity. Unlabeled atoms are carbon……...85 31 4.7: P NMR for 5, 5’-[(PPh3)Au]2-2, 2’-bithiophene…………………………………..90 1 4.8: H NMR for 5, 5’-[(PPh3)Au]2-2, 2’-bithiophene…………………………………...91 4.9: Mass Spectra of 5, 5’-[(PPh3)Au]2-2, 2’-bithiophene……………………………….92 vii List of Schemes Chapter 3. 3.1 Transmetalation reactions of pyrene…………………………………………………49 3.2 Ir catalyzed borylation of pyrene. (a) 2-(Bpin)pyrene, (b) 2,7-(Bpin)2pyrene………50 3.3: Auration of pyrene…………………………………………………………………..53 Chapter 4. 4.1: Auration of thiophene……………………………………………………………….83 viii Acknowledgements I would first like to thank
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