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University of Nevada, Reno The Design and Synthesis of Monomers for use in Two- Dimensional Polymerizations A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry by Dustin Day Patterson Dr. Benjamin T. King/Dissertation Advisor August 2017 UNIVERSITY OF NEVADA RENO THEGRADUATE SCHOOL We recommend that the dissertation prepared under our supervision by DUSTIN DAY PATTERSON Entitled The Design And Synthesis Of Monomers For Use in Two-Dimensional Polymerizations be accepted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Benjamin T. King, Ph.D., Advisor Robert S. Sheridan, Ph.D., Committee Member Christopher S. Jeffrey, Ph.D., Committee Member Lora Richards, Ph.D., Committee Member Glenn Miller, Ph.D., Graduate School Representative David W. Zeh, Ph. D., Dean, Graduate School August 2017 i Abstract The Design and Synthesis of Monomers for Two-Dimensional Polymerizations Dustin Day Patterson Ph.D. Advisor: Professor Benjamin T. King The focus of this dissertation is the design and synthesis of monomers for use in the synthesis of two dimensional polymers (2DPs). 2DPs can be described as laterally connected repeat units which cover a plane with no gaps or overlaps. Monomers used for the synthesis of 2DPs must be designed with at least three reactive functional groups; this permits polymerization into a 2D sheet of repeat units. A total of seven different monomer designs were synthetically sought out. Three of the seven monomers, 1-H, 1-MeO, and 1-F are previously reported and their synthesis was improved upon. Synthesis of three novel monomers, 1-FOH, 1-FPOH, and 1-PZn was attempted with the completion of two of the three targets 1-FOH, 1-PZn and a known derivative, 1-P. The above monomers were designed with anthraceno functionalities intended to undergo [4+4] cycloadditions during solid state and air-water interface polymerizations. The monomers intended for polymerization at the air-water interface (1-FOH, 1-FPOH and 1-PZn) were designed with synthetic handles for attachment of a hydrophilic substituent. A pyridine-DEG ligand was synthesized to ligate 1-PZn at the air-water interface. Growth of single crystals of 1-P and 1-H:C70 co-crystals were grown and irradiated at 365 nm, 400 nm, and 465 nm at 100 K-250 K. However, no polymerization occurred because a proper packing motif allowing a topochemical 2D polymerization was not achieved. Monomer, 1-pyz, was synthesized using a novel route which takes advantage of Suzuki coupling chemistry. 1-pyz possesses three pyrazole functionalities intended to undergo ii coordination with a metal center during polymerization. Monomer 1-pyz relies on reversible coordinative bonding in solution to form a metal coordinated lamellar crystal that can be exfoliated into single 2DP sheets. The highly insoluble monomer was reacted with various Ag, Au, and Mn salts under high temperature and superheated high pressure conditions towards polymerization. A single crystal containing metal coordinated layers of 1-pyz has yet to be realized. iii This thesis is dedicated: to my friends and family for their support and encouragement to my lab mates, past and present to my advisor, Professor Benjamin T. King iv Acknowledgements I would like to acknowledge all the people that have made this dissertation possible: Professor Benjamin T. King, for being an excellent advisor and all of your training during these past five years. For brining me out of my comfort zone and making me a better chemist whether I knew it or not at the time. And showing me a different way of learning and approaching problems. Professor Christopher Jeffrey, for your support and sharing of knowledge that has made me a more well-rounded chemist. And for serving as a doctoral committee member. Professor Robert Sheridan, for your support, willingness to help, and teaching one of my favorite classes (photochemistry). And for serving as a doctoral committee member. Professor Lora Richards and Professor Glenn Miller for serving as doctoral committee members. Dr. Sarah A. Cummings, for mentoring me as a teaching assistant, and giving me the opportunity to teach CHEM 220. Professor Vincent Catalano, for his invaluable help and training with the X-ray diffractometer, and help with solving crystal structures. Dr. Stephen Spain, for training and helping with instrumentation. Jennifer Heck, for being able to solve any problem you bring to her. My parents, for their continuous support and encouragement. My family, for their support, encouragement, and enthusiasm. Dr. Johnson, Dr. Bergkamp, Dr. Bridgewater, Dr. Buttrick, Mike Leonard, Mike Walley, Tom Brown, Rob Gilley, Daniel Murray, and Allyissa Murray, for their friendship, support, encouragement, and help throughout my education. William Thompson, for his friendship, support, motivation, and time spent helping with my OP and thesis. v King group members (past and present), for the camaraderie and all I have learned for you. The Chemistry Department at the University of Nevada, Reno All of my Friends vi Table of Contents Page Abstract ...................................................................................................................................... i Dedication ................................................................................................................................ iii Acknowledgements .................................................................................................................. iv Table of Contents ..................................................................................................................... vi List of Figures ............................................................................................................................. x List of Schemes ....................................................................................................................... xiii List of Tables ........................................................................................................................... xvi Chapter 1: Introduction ............................................................................................................. 1 1.1. One-Dimensional Polymers .................................................................................. 1 1.2. Two-Dimensional Polymers .................................................................................. 3 1.3. Synthetic Approaches to Two-Dimensional Polymers ......................................... 6 1.3.1. Ultra-High Vacuum Approach ............................................................... 6 1.3.2. Two-Dimensional Covalent Organic Framework ................................. 8 1.3.3. Single Crystal Approach ........................................................................ 9 1.3.4. Air-Water Interface Approach ............................................................ 18 1.4. Applications of Two-Dimensional Polymers ...................................................... 21 1.4.1. Separation ........................................................................................... 21 1.4.2. Scaffolds .............................................................................................. 23 1.5. Aim of the Dissertation ....................................................................................... 25 1.6. Overview of Chapters ......................................................................................... 26 Summary of Chapter 2. ................................................................................. 26 Summary of Chapter 3. ................................................................................. 28 Summary of Chapter 4. ................................................................................. 29 vii Summary of Chapter 5. ................................................................................. 30 Summary of Chapter 6. ................................................................................. 31 References .................................................................................................................. 31 2. Synthetic Routes Towards Four Structurally Related Monomers ..................................... 33 2.1. Overview ............................................................................................................. 33 2.2. Previous Work ..................................................................................................... 37 2.3. Results and Discussion ........................................................................................ 41 2.3.1. Aromatization with DARCO ................................................................ 42 2.3.2. X-ray Data of Regioisomer .................................................................. 44 2.3.3. One-Step Diels-Alder Approach .......................................................... 47 2.3.4. Two-Step Diels-Alder Approach ......................................................... 51 2.3.5. Bromination ........................................................................................ 53 2.3.6. Furan-Adduct ....................................................................................... 54 2.3.7. Sulfolene Reaction .............................................................................. 55 2.3.8. Dehydration and Oxidation ................................................................ 56 2.3.9. Fluorinated One-Step Diels-Alder Approach .....................................
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