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Information to Users INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. University Microfilms International A Beil & Howell Information Company 300 North Zeeb Road Ann Arbor. Ml 48106-1346 USA 313 761-4700 800 521-0600 Order Number 9120697 Photochemistry of dinuclear organoiron compounds: You can tune a piano, but can you tune a Fip? McKee, Steven D., Ph.D. The Ohio State University, 1991 UMI 300 N. Zeeb Rd. Ann Arbor, MI 48106 NOTE TO USERS THE ORIGINAL DOCUMENT RECEIVED BY U.M.I. CONTAINED PAGES WITH SLANTED AND POOR PRINT. PAGES WERE FILMED AS RECEIVED. THIS REPRODUCTION IS THE BEST AVAILABLE COPY. PHOTOCHEMISTRY OF DINUCLEAR ORGANOIRON COMPOUNDS. YOU CAN TUNE A PIANO, BUT CAN YOU TUNE A FIP? DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Steven D. McKee, B. S., M. S. ***** The Ohio State University 1991 Dissertation Committee: Approved by Dr. Bruce E. Bursten Dr. Matthew S. Platz Dr. Andrew Wojcicki Adviser Department of Chemistry To My Family and Catherine ACKNOWLEDGEMENTS I would like to express my sincere gratitude to those individuals who have helped me in this endeavor. I want to thank my advisor, Bruce Bursten and all of the members of the Bursten group, both past and present for a stimulating environment in the pursuit of this project. I am also indebted to the generosity of Professor Matt Platz and all of the members of his research group, both past and present for their help in the laser flash photolysis experiments that largely made this project come together. Without listing those individuals, I would like to thank the Brat-Pack and the Second Floor Evans crew for making the time spent here very enjoyable. I would also like to thank Catherine for her understanding during this long ordeal. VITA April 22, 1960 ..................................................... Bom - Lewistown, Pennsylvania May, 1983 .............................................................. B. S., Elizabethtown College, Elizabethtown, Pennsylvania May, 1985 ....................................... '..................... M. S., Bucknell University Lewisburg, Pennsylvania Sept., 1985 - March, 1987 .................... Teaching Associate Department of Chemistry The Ohio State University April., 1987 - Dec, 1990 ........................ Research Associate Department of Chemistry The Ohio State University PUBLICATIONS "Photochemical Insertion of Alkynes into Cp 2 F e 2 (CO) 2 (n*C O ) 2 : A Mechanistic Study by Laser Flash Photolysis." B. E. Bursten, S. D. McKee and M. S. Platz. J. Am. Chem. Soc. 1989, ill, 3428. "Electronic Structure of CpPtMej and Cp*PtMe 3 from UV Photoelectron Spectra." D. S. Yang, G. M. Bancroft, R. J. Puddephatt, B. E. Bursten and S. D. McKee Inorg. Chem. 1989. 28. 872. "Photochemistry of a p-AIkylidene Piano-Stool Dimer." S. D. McKee and B. E. Bursten J. Am. Chem. Soc. 1991. 113. 0000. "Photochemistry of Dinuclear Hydrocarbyl-Bridged Organoiron Complexes." S. D. McKee and B. E. Bursten., 200th American Chemical Society National Meeting, Washington, D. C., August 26-31, 1990. "The Photochemistry of a Diiron p-Alkylidene Piano-Stool Dimer." S. D. -McKee, B. E. Bursten and M. S. Platz., 198th American Chemical Society National Meeting, Miami Beach, Florida, September 10-15, 1989. "Theoretical and Experimental Studies of the Photochemistry of Organometallic Piano-Stool Dimers." B. E. Bursten, R. H. Cayton and S. D. McKee., 198th American Chemical Society National Meeting, Miami Beach, Florida, September 10-15, 1989. "Photochemistry of Dinuclear Organoiron Complexes." S. D. McKee, B. E. Bursten and M. S. Platz., 21st American Chemical Society Central Regional Meeting, Cleveland, Ohio, May 31-June 2, 1989. "Laser Flash Photolytic Studies of the Reaction of Alkynes with Cp 2 F c 2 (CO) 2 (p- CO)2 ." S. D. McKee, B. E. Bursten and M. S. Platz., 196th American Chemical Society National Meeting, Los Angeles, California, September 25-30, 1988. "Mechanistic Investigations of the Photochemical Insertion of Alkynes into C p 2 Fe2 (CO)2 (p-C O ) 2 -" S. D. McKee, B. E. Bursten and M. S. Platz., 20th American Chemical Society Central Regional Meeting, Morgantown, West Virginia, June 1-3, 1988. v "Three-Legged Piano-Stool Systems: A Comparison of Ligand Influences in CpML^ (L = O, CHj, CO) Complexes." S. D. McKee, B. E. Bursten and R. H. Cayton., 19th American Chemical Society Central Regional Meeting, Columbus, Ohio, June 24-26, 1987. FIELDS OF STUDY Major Field: Chemistry Experimental Organometallic Chemistry and Theoretical Chemistry. The Ohio State University; Professor Bruce E. Bursten, Advisor. TABLE OF CONTENTS ACKNOWLEDGEMENTS............................................................................................ iii VITA................................................................................................................................... iv LIST OF TABLES.......................................................................................................... xi LIST OF FIGURES........................................... x iv CHAPTER PAGE I INTRODUCTION............................................................................................... 1 Electronic Absorption Spectroscopy ..................................... 1 The Study of Reaction Mechanisms and Photochemical Methods ................................................. 7 Photochemistry of Dinuclear Organometallic Compounds ............................................................................. 11 Proposal ................................................................................................ 23 II MECHANISTC INVESTIGATION OF THE ALKYNE INSERTION REACTION IN Cp 2 Fe2 (CO)2 (p-CO )2 .............................. 26 Laser Flash Photolysis Studies of Cp 2 Fe2 (CO)2 (p-CO)2. Some Initial Considerations ........................................................ 28 Laser Flash Photolysis Studies of C p 2 Fe2 (CO)2 (p.-CO ) 2 with Alkynes ......................... 38 Product Studies of Cp 2 Fe2 (C O )2 (p.-CO ) 2 with Alkynes ......................................................................... 46 General Conclusions ....................................................................... 5 I Diphenylacetylene and Other Synthetic Anom alies .............................................................................. 55 III PHOTOCHEMICAL INVESTIGATION OF (Cp 2 SiM e2 )Fe2 (CO)2 (n-CO ) 2 ................................................................... 64 Photolysis of (Cp 2 SiM e2 )F e 2 (CO)2 (lt-C O >2 with HC=CC 6 H5 ................................................................. 65 LFP and Matrix Isolation Studies on (Cp 2 SiM e2 )Fe2 (CO)2 (li-CO ) 2 ....................................... 79 Some Final Thoughts on the Photochemistry of (Cp 2 SiM e2 )Fe2 (CO)2 (|i-C O ) 2 .................................. 87 IV PHOTOCHEMICAL INVESTIGATION OF Cp 2 Fe2 (CO)2 (li-CO)(p-CHCH 3 )................................................................ 91 Initial Consideration of Cp 2 Fe2 (CO)2 (li-CO)(tt-CHCH 3 ).................................... 92 Radical Formation Studies ........................................................... 92 Flash Photolysis and Matrix Isolation Experiments .......................................................................... 102 Reactions of [CpFe] 2 (jt-CO)2 (M--CHCH3 )............................... 117 Concluding Remarks ...................................................................... 136 V EXPERIMENTAL SECTION........................................................................ 146 General Procedures ......................................................................... 146 Solvent Purification ........................................................................ 148 Deuterated Solvents ........................................................................ 150 Reagents ............................................................................................... 151 Reaction Chemistry ......................................................................... 153 Irradiation of Cp 2 Fc2 (CO)2 (|i-C O ) 2 with phenylacetylene ....................................... 153 viii Irradiation of Cp 2 Fc 2 (CO>2 (n-C O
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