Synthesis and Application of Functionalized Diene-Based Polymers by Yue Yang A dissertation submitted to the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry Chapel Hill 2006 Approved by Advisor: Valerie Ashby Reader: Joseph DeSimone Reader: Jeffrey Johnson Reader: Mark Schoenfisch Reader: Sergei Sheiko UMI Number: 3207414 3207414 2006 UMI Microform Copyright All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, MI 48106-1346 by ProQuest Information and Learning Company. ii © 2006 Yue Yang ALL RIGHTS RESERVED iii ABSTRACT Yue Yang: Synthesis and Application of Functionalized Diene-Based Polymers (Under the direction of Dr. Valerie Ashby) A series of disubstituted functionalized dienes have been synthesized and polymerizations have been attempted. Functional groups that were incorporated into the monomers included primary amine, tertiary amine, piperidyl and methoxy groups. Among these, the dimethylamine functionalized butadienes were of the most interest and proved to have the greatest potential to be polymerized. Both free radical and anionic polymerizations have been investigated. The effect of various initiators, types of the solvent, temperature, size of the side groups and chain transfer reactions on free radical and anionic polymerizations was studied in detail. These polymers were evaluated for their potential as gene delivery vectors. Cytotoxicity, binding affinity and transfection efficiency properties were examined. A systematic study of the structure-property relationships revealed that cytotoxicity decreased as the side group of the polymers was altered. The binding affinity between the polymers and DNA also decreased as the size of the side group increased. Of the polymers studied, poly[2-(N,N-diethylaminomethyl)-1,3-butadiene], with lower cytotoxicity than poly(ethylene imine) and reasonable transfection efficiency at an N/P ratio of 2, is a promising, novel transfection vector. iv To my parents, Meicai and Mingyuan Yang, for their love and support v TABLE OF CONTENTS LIST OF TABLES vii LIST OF FIGURES viii LIST OF SCHEMES x Chapter 1: GENERAL INTRODUCTION 1.1 Introduction to Functional Materials 1 1.1.1 End-functionalization approach 1 1.1.2 Post-polymerization approach 6 1.1.3 Functionalized monomer approach. 10 1.2 Amine Functionalized Polymers as Gene Delivery Vectors 14 1.3 Dissertation Organization 17 1.4 Reference 18 Chapter 2: SYNTHESIS OF DISUBSTITUTED DIENE-BASED POLYMERS 2.1 Abstract 21 2.2 Introduction 21 2.3 Experimental 25 2.4 Results and Discussion 31 2.5 Conclusion 50 vi 2.6 Reference 51 Chapter 3: SYNTHESIS OF AMINE FUNCTIONALIZED DIENE- BASED POLYMERS AS NOVEL GENE DELIVERY VECTORS 3.1 Abstract 53 3.2 Introduction 53 3.3 Experimental 54 3.4 Results and Discussion 62 3.5 Conclusion 82 3.6 Acknowledgement 82 3.7 Reference 83 Chapter 4: GENERAL CONCLUSION 85 APPENDIX A. SUPPLEMENTAL MATERIALS FOR CHAPTER 2 89 APPENDIX B. SUPPLEMENTAL MATERIALS FOR CHAPTER 3 120 vii LIST OF TABLES Table Page 2-1. Bulk free radical polymerization of 2,3-bis(dimethyl- aminomethyl)-1,3-butadiene 40 2-2. Bulk free radical polymerization using t-BPO as initiator at 130 °C 41 2-3. Solution free radical polymerization using t-BPO as initiator at 130 °C 42 2-4. Solution radical polymerization using t-BPO as initiator at 130 °C, monomer:solvent (v/v) = 4:1 45 2-5. Solution radical polymerization using t-BPO as initiator at 130 °C for 24 h, monomer : THF (v/v) = 4:1 46 2-6. Free radical polymerization using t-BPA as initiator at 105 °C 46 3-1. Results of anionic polymerization of monomers I, II and III 64 3-2. Molecular weight characterization of free radical polymerization of amine functionalized monomers 72 viii LIST OF FIGURES Figure Page 1-1. Structure of end-functionalized polystyrene and polybutadiene 3 1-2. Structures of N-chloro initiators 6 1-3. Structures of silyl-functionalized butadiene monomers 11 1-4. Structures of functionalized diene monomers 11 1-5. Structures of PEI and PLL 17 2-1. Structures of nitrile functionalized monomers 36 2-2. 1 H NMR spectrum of 2,3-bis(dimethylaminomethyl)-1,3-butadiene 38 2-3. 1 H NMR spectrum of poly[2,3-bis(dimethylaminomethyl)-1,3- butadiene] 39 2-4. Structures of Diels-Alder dimers 40 2-5. Chelate structure of 2,3-bis(dimethylaminomethyl)-1,3- butadiene and lithium 47 2-6. Structures of nickel catalysts for metathesis polymerization 48 2-7. Glass transition temperature of functionalized diene-based polymers 49 3-1. Possible side reactions to terminate the chain propagation 68 3-2. 1 H NMR of poly[2-(N,N-diethylaminomethyl)-1,3-butadiene] prepared at (a) 10 ºC, (b) -5 ºC, (c) -40 ºC 70 3-3. Structure of polydienes chain end 71 3-4. Structure of PAI chain end 71 ix 3-5. Cytotoxicity of the polymers in vitro 77 3-6. Agarose gel electrophoresis assay 79 3-7. Transfection efficiency of various polymers 81 [...]...LIST OF SCHEMES Schemes Page 1-1 Synthesis of metallo-supramolecular block copolymers .4 1-2 Synthesis of 4-arm functionalized polymers 5 1-3 Nucleophilic aromatic substitution of poly(4-fluoro-2,5benzophenone) with various nucleophiles .7 1-4 Synthesis of functionalized polythiophenes 8 1-5 Synthesis of functionalized PLA and PCL 9 1-6 Synthesis of functional... reactions to form PEG homopolymers .74 3-5 Synthesis of PAI-b-PEG copolymer by free radical polymerization .75 3-6 Structures of MTS tetrazolium compound and the formazan product 76 4-1 Synthesis of functionalized diacid monomer .86 4-2 Synthesis of amine functionalized diene-based monomers 87 4-3 Synthesis of amine functionalized polyurethanes 88 xi CHAPTER... 1-6 Synthesis of functional polyesters In the following chapters, the functionalized monomer approach is used to prepare functionalized diene-based materials Synthesis of a wide variety of functionalized diene monomers is described Polymerizations via free radical and anionic techniques are discussed and the potential applications of the materials as gene delivery vectors are investigated 1.2 Amine Functionalized. .. functional polyesters .14 2-1 Synthesis of 2,3-bis(piperidylmethyl)-1,3-butadiene 32 2-2 Synthesis of 2-bromomethyl-1,3-butadiene .33 2-3 Synthesis of 2,3-bis(bromomethyl)-1,3-butadiene by sulfonation method .33 2-4 Synthesis of 2,3-bis(bromomethyl)-1,3-butadiene 34 2-5 Synthesis of functionalized dienes .35 2-6 Synthesis of 2,3-bis(dimethylaminomethyl)-1,3-butadiene... post-polymerization and polymerization of functionalized monomers, can also be used in combination Mecerreyes et al utilized the functionalized monomer and post polymerization approaches for the synthesis of functionalized polyesters (Scheme 1-6).37 These biodegradable polyesters have wide usage in commodity thermoplastics and in bioapplications First, the allyl functionalized monomer was synthesized by oxidation of. .. describes the synthesis and characterization of a wide variety of functionalized diene compounds and the free radical polymerization of the amine derivatives Effects of both solvents and initiators on the results of the polymerization are discussed The last chapter describes the anionic polymerization of 2-(N,N-dialkylaminomethyl)-1,3-butadienes and discusses their potential application as gene delivery... increasing the degree of polymerization Herein, the synthesis of a wide variety of disubstituted dienes is described Among these monomers, the amine -functionalized diene monomers are of the most interest due to their chemical and structural versatility Moreover, ionomers and polyelectrolytes can be obtained by partially or completely quaternizing the amine functionalized polymers These types of materials have... reported the synthesis of functionalized poly(lactic acid)s (PLA) and poly(caprolactone)s (PCL) for biomedical applications (Scheme 1-5).16 Functional groups that were incorporated include allyl, hydroxyl, carboxylic acid and acyl chloride group Generally a decrease of the molecular weight was observed in the at each step of the postpolymerization reactions This was attributed to the hydrolysis of the ester... Structures of PEI and PLL 1.3 Dissertation Organization This dissertation is organized into three chapters The first chapter is the general introduction to functionalized materials and gene therapy Three approaches, post- polymerization, end-functionalization and polymerization of functionalized monomers, are discussed The basic concept of gene delivery is introduced The second chapter describes the synthesis. .. Scheme 1-5 Synthesis of functionalized PLA and PCL 9 O O O = 2500 O 1.1.3 Functionalized monomer approach The third approach to synthesize functionalized materials is by polymerization of the functionalized monomers This method allows the functional groups to be uniformly incorporated into the polymer chain with each repeat unit having at least one functional group However, the effect of the functional . nucleophiles 7 1-4. Synthesis of functionalized polythiophenes 8 1-5. Synthesis of functionalized PLA and PCL 9 1-6. Synthesis of functional polyesters 14 2-1. Synthesis of 2,3-bis(piperidylmethyl)-1,3-butadiene. Information and Learning Company. ii © 2006 Yue Yang ALL RIGHTS RESERVED iii ABSTRACT Yue Yang: Synthesis and Application of Functionalized Diene-Based Polymers (Under the direction of Dr Structure of end -functionalized polystyrene and polybutadiene 3 1-2. Structures of N-chloro initiators 6 1-3. Structures of silyl -functionalized butadiene monomers 11 1-4. Structures of functionalized