BearWorks MSU Graduate Theses Summer 2018 Electrogenerated Chemiluminescence of Transition Metal Octaethylporphyrin and Tetraphenylporphyrin/Tri-n-Propylamine System Jamie Lee Gray Missouri State University, [email protected] As with any intellectual project, the content and views expressed in this thesis may be considered objectionable by some readers. However, this student-scholar’s work has been judged to have academic value by the student’s thesis committee members trained in the discipline. The content and views expressed in this thesis are those of the student-scholar and are not endorsed by Missouri State University, its Graduate College, or its employees. Follow this and additional works at: https://bearworks.missouristate.edu/theses Part of the Chemicals and Drugs Commons, and the Chemistry Commons Recommended Citation Gray, Jamie Lee, "Electrogenerated Chemiluminescence of Transition Metal Octaethylporphyrin and Tetraphenylporphyrin/Tri-n-Propylamine System" (2018). MSU Graduate Theses. 3280. https://bearworks.missouristate.edu/theses/3280 This article or document was made available through BearWorks, the institutional repository of Missouri State University. The work contained in it may be protected by copyright and require permission of the copyright holder for reuse or redistribution. For more information, please contact [email protected]. ELECTROGENERATED CHEMILUMINESCENCE OF TRANSITION METAL OCTAETHYLPORPHYRIN AND TETRAPHENYLPORPHYRIN/TRI-N- PROPYLAMINE SYSTEMS A Masters Thesis Presented to The Graduate College of Missouri State University TEMPLATE In Partial Fulfillment Of the Requirements for the Degree Master of Science, Chemistry By Jamie Lee Gray August 2018 Copyright 2018 by Jamie Lee Gray ii ELECTROGENERATED CHEMILUMINESCENCE OF TRANSITION METAL OCTAETHYLPORPHYRIN AND TETRAPHENYLPORPHYRIN/TRI-N- PROPYLAMINE SYSTEM Chemistry Missouri State University, August 2018 Master of Science Jamie Lee Gray ABSTRACT The electrogenerated chemiluminescence (ECL) of octaethylporphyrin (OEP), tetraphenylporphyrin (TPP) and a series of metal-ligand porphyrin complexes (Zinc, Copper, Palladium, Platinum, Ruthenium, Vanadium, Cobalt and Nickel) in CH2Cl2 is reported. ECL was generated upon sweep to positive potentials using tri-n-propylamine (TPrA) as an oxidative-reductive coreactant. ECL efficiencies were between 0.010 and 0.770 using Ru(bpy)3(PF6)2 (bpy = 2,2’-bpyridine) as a relative standard (ecl = 1). The ECL intensity peaks at a potential corresponding to oxidation of the complexes and TPrA, suggesting that the same excited states are formed in both photoluminescence and ECL. Although the ECL was weaker than corresponding PL efficiencies, similar trends were observed in both experiments, again suggesting identical excited states are formed. KEYWORDS: electrogenerated chemiluminescence, ECL, metalloporphyrins, coreactants, porphyrin This abstract is approved as to form and content _______________________________ Mark M. Richter, Ph.D. Chairperson, Advisory Committee Missouri State University iii ELECTROGENERATED CHEMILUMINESCENCE OF TRANSITION METAL OCTAETHYLPORPHYRIN AND TETRAPHENYLPORPHYRIN/TRI-N- PROPYLAMINE SYSTEM By Jamie Lee Gray A Masters Thesis Submitted to the Graduate College Of Missouri State University In Partial Fulfillment of the Requirements Master of Science, Chemistry August 2018 Approved: _______________________________________ Mark Richter, PhD _______________________________________ Kevin Evans, PhD _______________________________________ Erich Steinle, PhD _______________________________________ Gautam Bhattacharyya, PhD _______________________________________ Julie Masterson, PhD: Dean, Graduate College In the interest of academic freedom and the principle of free speech, approval of this thesis indicates the format is acceptable and meets the academic criteria for the discipline as determined by the faculty that constitute the thesis committee. The content and views expressed in this thesis are those of the student- scholar and are not endorsed by Missouri State University, its Graduate College, or its employees. iv ACKNOWLEDGEMENTS I would like to thank the following people for their help and support during the course of my undergraduate and graduate studies. Thanks to the Missouri State University Department of Chemistry for being my home for the past 5 years, as well as the Graduate College for assisting in the funding of my research and education. Thank you to Dr. Gautam Bhattacharyya, Dr. Katye Fichter, Dr. Kevin Evans and Dr. Erich Steinle for being on my graduate committee, and for their advice and guidance. Thank you to my advisor and mentor, Dr. Mark Richter. He was the person who helped guide me through my undergraduate and graduate coursework, as well as his unending patience with me during the years of research we have had together. My sincere appreciation goes out to all of the friends I have made during the past 5 years I have spent at Missouri State University, to the countless hours spent on homework, studying and procrastination, I truly love all of you. Finally to my husband, to whom I owe everything. v TABLE OF CONTENTS Chapter 1: Introduction to Electrogenerated Chemiluminescence ......................................1 Chapter 2: Experimental Methods .......................................................................................6 Materials ..................................................................................................................6 Methods....................................................................................................................6 Chapter 3: Metal Centered Porphyrins ..............................................................................10 Results and Discussion ..........................................................................................10 Conclusions ............................................................................................................25 Chapter 4: Future Work .....................................................................................................27 References ..........................................................................................................................28 Appendix ............................................................................................................................30 vi LIST OF TABLES + Table 1. Electrochemical oxidation (Ea) and re-reduction (Ec) potentials vs Ag/Ag reference electrode. 0.1mM complex, 0.05 M Bu4NPF6 in CH₂Cl₂. .................................11 Table 2. PL Efficiencies of porphyrin complexes. 0.01mM compound in CH2Cl2. 2+ Efficiencies were obtained using Ru(bpy)3 (ᶲPL = 0.042) as a standard ..........................14 Table 3. ECL Efficiencies of porphyrin complexes. 0.01mM compound in CH2Cl2; 2+ 0.05M TPrA; 0.05 M Bu4NPF6. Efficiencies were obtained using Ru(bpy)3 (ᶲECL = 1) as a standard.. .........................................................................................................................22 vii LIST OF FIGURES 2+ Figure 1. Proposed mechanism for Ru(bpy)3 /TPrA reaction sequence ............................3 Figure 2. Structures of OEP (left) and TPP (right); M=metal center ..................................4 Figure 3. Cyclic Voltammetry of 0.1 mM TPP and 0.05M Bu4NPF6 in CH₂Cl₂. .............12 Figure 4. Cyclic Voltammetry of 0.1 mM Cu(TPP), and 0.05M Bu4NPF6 in CH₂Cl₂. .....12 Figure 5. Cyclic Voltammetry of 0.1 mM OEP, and 0.05M Bu4NPF6 in CH₂Cl₂. ............12 Figure 6. Cyclic Voltammetry of 0.1 mM V(OEP), and 0.05M Bu4NPF6 in CH₂Cl₂. ......13 Figure 7. UV-Vis of 0.01mM OEP in CH₂Cl₂. ..................................................................15 Figure 8. UV-Vis of 0.01mM TPP in CH₂Cl₂. ...................................................................15 Figure 9. UV-Vis of 0.01mM Cu(TPP) in CH₂Cl₂. ...........................................................15 Figure 10. UV-Vis of 0.01mM V(OEP) in CH₂Cl₂. ..........................................................16 Figure 11. Photoluminescence of 0.01mM OEP in CH₂Cl₂. ..............................................16 Figure 12. Photoluminescence of 0.01mM TPP in CH₂Cl₂. ..............................................17 Figure 13. Photoluminescence of 0.01mM Cu(TPP) in CH₂Cl₂ ........................................17 Figure 14. Photoluminescence of 0.01mM V(OEP) in CH₂Cl₂ .........................................18 Figure 15. ECL intensity versus potential of 0.01mM OEP in CH₂Cl₂ (0.05M TPrA and 0.05 M Bu4NPF6). ..............................................................................................................20 Figure 16. ECL intensity versus potential of 0.01mM TPP in CH₂Cl₂ (0.05M TPrA and 0.05 M Bu4NPF6).. .............................................................................................................20 Figure 17. ECL intensity versus potential of 0.01mM Cu(TPP) in CH₂Cl₂ (0.05M TPrA and 0.05 M Bu4NPF6). .......................................................................................................21 Figure 18. ECL intensity versus potential of 0.01mM V(OEP) in CH₂Cl₂ (0.05M TPrA and 0.05 M Bu4NPF6). .......................................................................................................21 Figure 19. ECL intensity versus time of 0.01mM OEP in CH₂Cl₂ (0.05M TPrA and 0.05 M Bu4NPF6).. .....................................................................................................................23 viii Figure 20. ECL intensity