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Synthesis of Polycatenanes Through Molecular Design

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Synthesis of Polycatenanes Through Molecular Design SYNTHESIS OF POLYCATENANES THROUGH MOLECULAR DESIGN by QIONG WU Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Macromolecular Science and Engineering CASE WESTERN RESERVE UNIVERSITY January, 2017 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of Qiong Wu Candidate for the degree of Doctor of Philosophy. Committee Chair: Dr. Stuart Rowan Committee Member: Dr. Emily Pentzer Committee Member: Dr. Jon Pokorski Committee Member: Dr. Michael Hore Date of Defense: 08/24/2016 Table of Contents Chapter 1. Introduction ..................................................................................................... 1 1. The Topological Bond ............................................................................................................... 1 2. The Synthetic Approach of Topologically Bonded Molecules .................................................... 3 2.1 Statistical Approach ................................................................................................................ 3 2.2 Templated Synthesis ............................................................................................................... 4 3. Macromolecules Containing Topological Bonds ........................................................................ 7 4. Main-chain Polyrotaxanes and Slide-ring Materials .................................................................. 9 4.1 Synthesis of Poly[n]rotaxanes ................................................................................................ 9 4.2 Applications of poly[n]rotaxanes .......................................................................................... 11 4.3 Slide-ring gels (SLGs) and Slide-ring materials (SLMs) .......................................................... 16 5. Topological main-chain polyrotaxanes ................................................................................... 22 6. Main-chain polycatenanes ..................................................................................................... 23 6.1 Poly[n]catenane .................................................................................................................... 23 6.2 Main-chain poly[2]catenane ................................................................................................. 27 6.3 Radial polycatenane ............................................................................................................. 29 7. Side-chain polyrotaxanes and polycatenanes ......................................................................... 30 8. Interlocked polymeric materials ............................................................................................. 30 9. Polycatenane network ........................................................................................................... 32 10. Conclusion ......................................................................................................................... 33 Chapter 2. Optimizing the Formation of [3]Catenane through Molecular Design† ............. 41 1. Introduction ........................................................................................................................... 41 i 2. The Effect of the Linker Group on the Thread ......................................................................... 45 3. The Effect of Side Chain Bulkiness of the Macrocycle ............................................................. 48 4. Isolation and characterization of [3]catenane 8. ..................................................................... 52 5. Conclusion ............................................................................................................................. 56 6. Experimental .......................................................................................................................... 57 6.1 Materials and Methods ........................................................................................................ 57 6.2 Synthesis of Precursors and Components ............................................................................ 58 Chapter 3. Templated Synthesis toward Bip-containing Polymers and Catenanes ............ 70 1. Introduction ........................................................................................................................... 70 2. Results and Discussion ........................................................................................................... 72 2.1 The metallo-supramolecular polymer .................................................................................. 72 2.2 The ring-closing metathesis (RCM) reaction ......................................................................... 77 2.3 Isolation of Bip-containing polymer and catenanes. ............................................................ 83 2.4 The formation of polymer 17 and the improvement toward polycatenane ........................ 85 2.5 Comparison with the Biphenyl-linked Monomer 16 ............................................................ 88 2.6 Synthesis templated by Fe-MSP ........................................................................................... 91 2.7 Hydrogenation of the double-bond ...................................................................................... 92 3. Conclusion ............................................................................................................................. 94 4. Experimental .......................................................................................................................... 95 4.1 Materials and Methods ........................................................................................................ 95 4.2 Synthesis of Components ..................................................................................................... 97 Chapter 4. The Synthesis of Poly[n]catenanes ................................................................ 106 1. Introduction ......................................................................................................................... 106 ii 2. The Synthesis and Characterization of Polycatenane ............................................................ 111 2.1 Component Design ............................................................................................................. 111 2.2 Polycatenane Synthesis and Purification ............................................................................ 113 2.3 Proof of Polycatenane Structure ........................................................................................ 121 2.4 Polycatenane Architecture Determination ......................................................................... 136 2.5 Metallo Response of Polycatenane .................................................................................... 153 2.6 Side-reaction and Improvements ....................................................................................... 154 3. Conclusion ........................................................................................................................... 156 4. Supporting Information ........................................................................................................ 157 4.1 Experimental Details ........................................................................................................... 157 4.2 Supplementary Figures and Tables. .................................................................................... 165 Chapter 5. Synthesis of Poly[n]catenane using Fe2+ as Templating Metal ....................... 173 1. Introduction ......................................................................................................................... 173 2. Synthesis of Polycatenane Templated with Fe2+ ................................................................... 174 3. Architecture Study of Fe2+ Templated Polycatenanes ........................................................... 176 3.1 Molecular weight ................................................................................................................ 176 4. Attempts to Improve the Synthesis ...................................................................................... 184 5. Conclusion ........................................................................................................................... 186 6. Supporting Information ........................................................................................................ 187 6.1 The assembly of Fe-alt-MSP ............................................................................................... 187 6.2 DOSY study of Fe-alt-MSP ................................................................................................... 189 6.3 The Synthesis of 22Fe (and 22Fe-Oligo) via RCM Reaction ...................................................... 190 6.4 Purification and Fractionation of Polycatenane ................................................................. 190 iii 6.5 GPC-MALLS and 1H-NMR Study .......................................................................................... 191 Chapter 6. Toward High-yield Synthesis of Linear Polycatenane ..................................... 192 1. Introduction ......................................................................................................................... 192 2. Macrocycle
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