Eastern Illinois University The Keep Masters Theses Student Theses & Publications 1997 Azo Dyes Based on 1,10-Phenanthroline Minchong Mao Eastern Illinois University This research is a product of the graduate program in Chemistry at Eastern Illinois University. Find out more about the program. Recommended Citation Mao, Minchong, "Azo Dyes Based on 1,10-Phenanthroline" (1997). Masters Theses. 1814. https://thekeep.eiu.edu/theses/1814 This is brought to you for free and open access by the Student Theses & Publications at The Keep. It has been accepted for inclusion in Masters Theses by an authorized administrator of The Keep. For more information, please contact [email protected]. THESIS REPRODUCTION CERTIFICATE TO: Graduate Degree Candidates (who have written formal theses) SUBJECT: Permission to Reproduce Theses The University Library is rece1v1ng a number of requests from other institutions asking permission to reproduce dissertations for inclusion in their library holdings. Although no copyright laws are involved, we feel that professional courtesy demands that permission b~ obtained from the author before we allow theses to be copied. PLEASE SIGN ONE OF THE FOLLOWING STATEMENTS: Booth Library of Eastern Illinois University has my permission to lend my thesis to a reputable college or university for the purpose of copying it for inclusion in that institution's library or research holdings. I respectfully request Booth Library of Eastern Illinois University not allow my thesis to be reproduced because: Author Date Azo Dyes Based on 1,10-Phenanthroline (TITLE) BY Minchong Mao THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master of Science in Chemistry IN THE GRADUATE SCHOOL, EASTERN ILLINOIS UNIVERSITY CHARLESTON, ILLINOIS 1997 YEAR I HEREBY RECOMMEND THIS THESIS BE ACCEPTED AS FULFILLING THIS PART OF THE GRADUATE DEGREE CITED ABOVE Azo Dyes Based on 1,10-Phenanthroline Approved by Thesis Committee: Dr. Mark E. McGuire Date Dr. Ellen A. Keiter Date Date Abstract Title of Thesis: Azo Dyes Based on 1,10-Phenanthroline. Name: Minchong Mao Thesis directed by: Dr. Mark E. McGuire A series of new phenanthroline based azo-dye ligands, produced by diazotizing 5- amino-1, 10-phenanthroline (5-NHrphen) and then coupling this intermediate to a variety of coupling components, has been synthesized and characterized. The coupling components used were P-naphthol, phenol, and 2,6-dimethylphenol, and the three dye ligands were named phen-azo-P-naphthol, phen-azo-p-phenol, and phen-azo-2,6- dimethylphenol, respectively. 1H-NMR and IR spectra showed that the dyes exist primarily in the azo form in DMSO solution and as solids. UV-Vis spectra (in MeOH) showed intense (i:: =10 4 M-1cm- 1) absorptions ranging from 380 nm to 500 nm for these ligands. The ligand phen-azo-p-phenol has been coordinated to a Re(I) metal center through the phenanthroline linkage to form a stable polypyridyl complex, /ac-Re1(C0)3(phen-azo-p-phenol)Cl. When compared to the well-known complex/ac­ Re1(C0)3(phen)Cl, the new Re(I)-dye complex shows a greatly enhanced visible absorption band in the 3 70 - 400 nm range. This absorption is primarily due to a ligand­ centered transition in the coordinated phen-dye ligand. Preliminary emission spectra (in MeOH) reveal that/ac-Re1(C0)3(phen-azo-p-phenol)Cl, unlike its Re(I)-phen analog, does not emit. Acknowledgments I would like to express my sincere and deep appreciation to Dr. Mark E. McGuire, my research advisor, for his knowledgeable guidance, great patience, and kind encouragement. I wish to thank Dr. Ellen A. Keiter for her help in instruction of operating the QE- 300 NMR spectrometer. Also, I would like to thank the faculty and staff of the Chemistry Department and the other members of our research group for their assistance. ii Table of Contents Abstract ............................................................................................................................... i Acknowledgments ............................................................................................................. ii Table of Contents .............................................................................................................. iii List of Tables .................................................................................................................... v List of Figures .................................................................................................................. vi Chapter page 1. Introduction .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 1 2. Experimental Materials .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 14 Synthesis .............................................................................................................. 14 Methods ................................................................................................................ 23 3. Results and Discussion Synthesis and Purification of Phenanthroline-Based Dyes .................................. 24 (1) A possible self-coupling reaction of 5-NH2-phen .......................................... 24 (2) Coupling temperature and pH value ............................................................... 26 (3) Starting materials I chromatographic materials .............................................. 28 (4) Elemental analysis .......................................................................................... 28 1H-NMR Spectra .................................................................................................. 29 (1) Starting materials ............................................................................................ 29 (2) Phen-azo-P-naphthol ...................................................................................... 29 (3) Phen-azo-p-phenol .......................................................................................... 32 (4) Phen-azo-2,6-dimethylphenol ........................................................................ 33 (5) Re(I) complexes ............................................................................................. 34 Ill Tab~ofCon~n~ ~onW) IR Spectra ............................................................................................................. 3 5 (1) Phen-dye ligands ............................................................................................ 35 (2) Re(I) complexes ............................................................................................. 36 UV-Vis Spectra .................................................................................................... 37 (1) Phen-dye ligands ............................................................................................ 37 (2) Re(I) complexes ............................................................................................. 39 Summary .............................................................................................................. 42 4. References ............................................................................................................ 98 IV List of Tables Table page 3-1 1H-NMR for 5-NOrphen, phen, and 5-NHrphen ..................................... 43 3-2 1H-NMR for 2,3,4,5,6-d phenyl-azo-P-naphthol and phenyl-azo-P-naphthol .................................................................... 44 3-3 1H-NMR for phen-azo-P-naphthol and related compounds ........................... 45 3-4 1H-NMR for phen-azo-p-phenol and related compounds ............................. 46 3-5 1H-NMR for phen-azo-2,6-dimethylphenol and related compounds ................ 47 1 3-6 H-NMR for Re\C0)3(phen)Cl, Re\C0)3(phen-azo-p-phenol)Cl and related compounds ......................................................................... 48 3-7 Carbonyl Stretching Frequencies in IR spectra ......................................... 49 3-8 UV-Vis data for phen-azo dye ligands and related compounds ...................... 50 v List of Figures Figures page 1-1 bpy and phen ................................................................................ 1 1-2 Relative disposition of metal and ligand orbitals and possible electronic transitions in an octahedral ligand field of a transition metal complex .............. 2 1-3 Schematic representation of various orbital disposition in strong-field (nd6) complexes [M(LL )3t+; LL = bpy ......................................................... 4 1-4 Overall process of an individual molecule capturing a photon of sunlight. ......... 5 1-5 Examples of multidentate polypyridyl ligands used in the synthesis of multimetallic polypyridyl complexes ..................................................... 6 1-6 Molecular orbital diagram for monometallic and bimetallic Ru(II) complexes .................................................................................... 6 1-7 Synthesis of phen-azo-dyes ................................................................. 9 1-8 Preparation of 5-NHrPhen ............................................................... 10 1-9 Mechanism of Diazotization ............................................................. 11 1-10 Mechanism of coupling reaction . .. .. 12 1-11 Synthesis ofRe(I) complexes containing phen and phen-azo phenol ................ 13 3-1 Self coupling reaction of amine .......................................................... 24 3-2