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Uni International 300 N THE SYNTHESIS AND REACTIVITY OF THE BIS-PHOSPHINE BRIDGED DI-IRON COMPLEX DI(CARBONYL - CYCLOPENTADIENYL-IRON-(N- BUTYL)) (BIS - DIPHENYLPHOSPHINOMETHANE). Item Type text; Thesis-Reproduction (electronic) Authors Eck, Charles Paul. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 01/10/2021 18:20:20 Link to Item http://hdl.handle.net/10150/274861 INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or "target" for pages apparently lacking from the document photographed is "Missing Page(s)". If it was possible to obtain the missing .page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. When an image on the film is obliterated with a round black mark, it is an indication of either blurred copy because of movement during exposure, duplicate copy, or copyrighted materials that should not have been filmed. For blurred pages, a good image of the page can be found in the adjacent frame. If copyrighted materials were deleted, a target note will appear listing the pages in the adjacent frame. 3. 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Zeeb Road Ann Arbor, Ml 48106 1321429 ECK, CHARLES PAUL THE SYNTHESIS AND REACTIVITY OF THE BIS-PHOSPHINE BRIDGED DI-IRON COMPLEX DI(CARBONYL - CYCLOPENTADIENYL-IRON-(N-BUTYL)) (BIS - DIPHENYLPHOSPHINOMETHANE) THE UNIVERSITY OF ARIZONA M.S. 1983 University Microfilms international 300 N. Zeeb Road, Ann Arbor, MI 48106 Copyright 1983 by ECK, CHARLES PAUL All Rights Reserved PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . 1. Glossy photographs or pages 2. Colored illustrations, paper or print 3. Photographs with dark background 4. Illustrations are poor copy 5. Pages with black marks, not original copy 6. Print shows through as there is text on both sides of page 7. Indistinct, broken or small print on several pages t/' 8. Print exceeds margin requirements 9. Tightly bound copy with print lost in spine 10. Computer printout pages with indistinct print 11. Page(s) lacking when material received, and not available from school or author. 12. Page(s) seem to be missing in numbering only as text follows. 13. Two pages numbered . Text follows. 14. Curling and wrinkled pages 15. Other University Microfilms International THE SYNTHESIS AND REACTIVITY OF THE BIS-PHOSPHINE BRIDGED DI-IRON COMPLEX DIICARBONYL-CYCLOPENTADIENYL-IRON-(n-BUTYL)] (BIS-DIPHENYLPHOSPHINOMETHANE) by Charles Paul Eck A Thesis Submitted to the Faculty of the DEPARTMENT OF CHEMISTRY In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 19 8 3 Copyright 1983 Charles Paul Eck STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may .be granted by the copyright holder. SIGNEDCux ?. tcX APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: 3 :GORY 0. NELSON Date Assistant Professor of Chemistry DEDICATION Trust in the Lord with all your heart, and do not rely upon your own insight. In all your ways acknowledge him, and he will make straight your paths. Be not wise in your own eyes; fear the Lord, and turn away from evil. (Proverbs 3:5-7) But grow in grace and knowledge of our Lord and Saviour Jesus Christ. To him be the glory both now and to the day of eternity. Amen. (2 Peter 3:18) The Holy Bible. Revised Standard Version. iii ACKNOWLEDGMENTS I choose to acknowledge Dr. Gregory Nelson for his guidance in these initial stages of my graduate career and for his example and influence, not only as my advisor, but as a friend also. Special appreciation is extended to Dr. Michael Wright for his helpful and considerate comments and evaluations during all of our interactions. Grateful acknowledgment is given to Mr. Carl Scott for the educational and time saving introduction into personal computers. With the love given to me from the Lord, I thank Ali for being my friend and loving wife. iv TABLE OF CONTENTS Page LIST OF ILLUSTRATIONS vii LIST OF TABLES viii ABSTRACT • ix CHAPTER 1. INTRODUCTION 1 1.1 Multinuclear Complexes 1 2. CARBENE COMPLEXES 7 2.1 Introduction—Mononuclear Carbene Complexes 7 2.2 Results and Discussion 8 2.2.1 Preparation of Bis-acyl Complexes VI-A,B,C . 10 2.2.2 Reaction of VI-A,B,C with Methyl Triflate . 11 3. CYCLOPENTADIENYL IRON CARBONYL PHOSPHINES AND IODIDES ... 17 3.1 Introduction 17 3.1.1 Reactions of [Cp Fe (CO)2]2 with Mono- and Bidentate Fhosphines 17 3.1.2 Oxidation of Di-iron Complexes with Halogen . 18 3.1.3 Reactions of [Cp Fe (CO)2 X] with Phosphines . 21 3.2 Results and Discussion 22 3.2.1 Synthesis of Dinuclear Bis-Phosphite Bridged Diiodide XX 23 3.2.2 Synthesis of Dinuclear Bis-Phosphine Bridged Diiodide XVIa 26 4. THERMAL DECOMPOSITION OF IRON ALKYLS 37 4.1 Introduction 37 4.1.1 3-Hydride Elimination 37 4.1.2 Bimolecular Decomposition 40 4.2 Results and Discussion 43 4.2.1 Preparation or Attempted Synthesis of Iron Alkyls and Iron Hydrides 43 4.2.2 Reactivities and Phosphine Equilibria .... 52 4.2.3 Thermal Decomposition of Complex XXIV .... 62 v vi TABLE OF CONTENTS—Continued Page 5. CONCLUSIONS 86 6. EXPERIMENTAL 88 6.1 General Data 88 6.2 Carbene Complexes 89 6.2.1 Preparation of Me2Si [Cp Fe (CO) L (COR)]2 (VI) 89 6.2.2 Reaction of VI with Methyl Triflate Followed by Reducing Agents 91 6.3 Cyclopentadienyl Iron Carbonyl Phosphines and Iodides 93 6.3.1 Preparation of [Cp Fe (CO)]2[(C^H^O)2P- CH2-P(OC6H5)2] (XXI) 93 6.3.2 Reaction of XXI with Iodine 95 6.3.3 Preparation of [Cp Fe (CO)]2[(CgH^)2P- CH2-P(CgH5)2] (Ilia) and the Reaction of Ilia with Iodine 96 c H p 6.3.4 Preparation of [Cp Fe (CO) I] f 6 5)2 ~" CH2-P(C6H5)2] (XVIII) and [Cp Fe (CO) I]2- H ) CH C H ] [(C6 5 2P- 2-P( 6 5)2 (XVIa) ". 96 6.3.5 Preparation of [Cp Fe (CO) ((CgHg^P- CH2-P(C6H5)2)][I] (XXIII) 98 6.4 Thermal Decomposition of Iron Alkyls 99 6.4.1 Reaction of XVIa with n-Butyl Lithium— Preparation of [Cp Fe (CO) (n-C^Hg)^- [CC6H5)2P-CH2"P(C6H5)2] <XXIV) an° [Cp Fe 7CO) (n-C4Hg)][(C6H5)2P-CH2- C H Fe co XX 99 P( 6 5)2] [°P ( > *1 ( X> 6.4.2 Preparation of [Cp Fe (CO) (n-C^Hg)]- [(C6H5)2P-CH2-P(C6H5)2] (XXV) 100 6.4.3 Preparation of [Cp Fe (CO) CH2-P(C6H5)2] (XXVI) 101 6.4.4 Preparation of [Cp2 Fe2 (CO)2 H]- XXIX) 102 [(C6H5)2P-CH2-P(C6H5)2] < 6.4.5 Reaction of XXIX with n-Butyl Lithium .... 102 6.4.6 Reaction of XXIX with Sodium Borohydride . 103 6.4.7 Reaction of XVIa with Lithium Aluminum Hydride 103 6.4.8 Reaction of XXV, XXVI and DPPM at 54°C .... 104 6.4.9 Thermal Experiments of XXIV 104 6.4.10 Phosphorus *^P NMR Thermal Time Course at 30°C and 50°C 106 REFERENCES 110 LIST OF ILLUSTRATIONS Figure Page 1. 250 MHz 1H NMR of Complex XVIII, 6 3.7-6 3.1 • 28 2. 250 MHz 1H NMR of Complex XXIII, 6 6.0-6 4.0 31 3. 250 MHz 1H NMR of Complex XVIa, 6 5.0-6 3.0 33 31 4. P NMR of Complex XVIa, 80-50 ppm 34 31 5. P NMR Spectrum of Complex XXIV 45 6.
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