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Synthesis and Reactions of 4,5-Homotropone and 4,5-Dimethylenetropone Richard Anthony Fugiel Iowa State University

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Synthesis and Reactions of 4,5-Homotropone and 4,5-Dimethylenetropone Richard Anthony Fugiel Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1974 Synthesis and reactions of 4,5-homotropone and 4,5-dimethylenetropone Richard Anthony Fugiel Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Fugiel, Richard Anthony, "Synthesis and reactions of 4,5-homotropone and 4,5-dimethylenetropone " (1974). Retrospective Theses and Dissertations. 5986. https://lib.dr.iastate.edu/rtd/5986 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORIVIATIOIM TO USERS This material was produced from a microfilm copy of the original document. While the most advanced technological means to photograph and reproduce this document have been used, the quality is heavily dependent upon the quality of the original submitted. The following explanation of techniques is provided to help you understand markings or patterns 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 thru an image and duplicating adjacent pages to insure you complete continuity. 2. When an image on the film is obliterated with a large round black mark, it is an indication that the photographer suspected that the copy may have moved during exposure and thus cause a blurred image. You will find a good image of the page in the adjacent frame. 3. When a map, drawing or chart, etc., was part of the material being photographed the photographer followed a definite method in "sectioning" the material. It is customary to begin photoing at the upper left hand corner of a large sheet and to continue photoing from left to right in equal sections with a small overlap. If necessary, sectioning is continued again — beginning below the first row and continuing on until complete. 4. The majority of users indicate that the textual content is of greatest value, however, a somewhat higher quality reproduction could be made from "photographs" if essential to the understanding of the dissertation. Silver prints of "photographs" may be ordered at additional charge by writing the Order Department, giving the catalog number, title, author and specific pages you wish reproduced. 5. PLEASE NOTE: Some pages may have indistinct print. Filmed as received. Xerox University Microfilms 300 North Zeeb Road Ann Arbor, Michigan 48106 74-15,426 FUGIEL, Richard Anthony, 1943- SYNTHESIS AND REACTIONS OF 4,5-HOMOTROPONE AND 4,5-DIMETHYLENETROPONE. Iowa State University, Ph.D., 1974 Chemistry, organic University Microfilms, A XEROX Company, Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED. Synthesis and reactions of 4,5-homotropone and 4,5-dimethylenetropone by Richard Anthony Pugiel A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment The Requirements for the Decree of DOCTOR OF PHILOSOPHY Department: Chemistry Major: Organic Chemistry Approved : Signature was redacted for privacy. In C ge of Majo Work Signature was redacted for privacy. For the Maj Signature was redacted for privacy. For the Graa ate College Iowa State University Ames, Iowa 1974 il TABLE OF CONTENTS Page PART I. SYNTHESIS AND REACTIONS OF 4,5-HOMOTROPONE 1 INTRODUCTION 2 LITERATURE REVIEW 5 RESULTS AND DISCUSSION 23 EXPERIMENTAL 67 General 67 Preparation of 2,5-dimethoxy-2,5-dihydrofuran 67 Preparation of 6,6-dichloro-2,4-diinethoxy-3- oxabicycIo[3.1-0]hexane 68 Preparation of 2,4-dimethoxy-3-oxabicyclo- [3.1.0]hexane 69 Preparation of 9-niethyl-9-azatricyclo- [3.3.1.0®>®]nonan-3-one 70 Attempted reactions of 2,5-dimethoxy-2,5- dihydrofuran with the Simmons-Smith reagent 7I Preparation of 6,6-dlchloro-2,4-dimethoxy-3- oxabicyclo[3.1.0]hexane via chloroform and potassium t-butoxide 72 Attempted reaction of 2,5-dimethoxy-2,5- dihydrofuran with phenyKbromodichloro- methyl)mercury 72 Preparation of bicyclo[6.1.0]nona-2,4,6-trlene 73 Preparation of 9-methyl-9-azatricyclo[3.3.1.0®®]- nonan-3-one via bicyclo[6.1.0]nona-2,4,6-triene 73 Preparation of 9,9-dlmethyl-3-oxo-9-azoniatri- cyclo[3.3.1.0 »®]nonane tosylate 74 Preparation of 4,5-homotropone 75 Hydrogénation of 4,5-homotropone J6 ill Page Preparation of the 4-hydroxyhoinotropyliuni cation 78 Basicity of 4,5-homotropone 78 Thermolysis of 4,5-homotropone in the vapor phase 79 Qualitative thermolysis of 4,5-homotropone and 2,4,6-cyclooctatrienone at 400° in the vapor phase 81 Photolysis of 4,5-homotropone in diethyl ether 8l Qualitative irradiation of 4,5-homotropone in methanol 82 Preparative photolysis of 4,5-homotropone in methanol 82 Qualitative irradiation of 4,5-homotropone and 2,4j6-cyclooctatrienone in methanol 83 Attempted reaction of 4,5-homotropone with dimethyl oxasulfonium methylide 83 Attempted reaction of 4,5-homotropone with hydrogen chloride and antimony pentachloride 84 PART II. SYNTHESIS AND REACTIONS OF 4,5-DIMETHYLENETROPONE 8 5 INTRODUCTION 86 LITERATURE REVIEW 88 RESULTS AND DISCUSSION IO8 EXPERIMENTAL 140 General 140 Preparation of blcyclo[6.2.0]deca-2,4,6-trlene 140 Preparation of lO-methyl-lO-azatricyclo- [4.3.1..0^> ®]decan-8-one l4l Iv Page Preparation of 10,10-dlmethyl-8-oxo-10- azoniatricyclo[4.3.1.0^ ^ ]decane tosylate 142 Preparation of blcyclo[5.2.0]nona-2,5-dlen-4- one 143 Thermolysis of bicyclo[5.2.0]nona-2,5-dien-8- one 144 Attempted dehydrogenation of bicyclo[5.2.0]- nona-2,5-dien-8-one with palladium on charcoal 145 Attempted dehydrogenation of bicyclo[5.2.0]- nona-2,5-dien-8-one with dichlorodicyanoquinone Preparation of 4,5-dimethylenetropane 145 Photolysis of 4,5-dimethylenetropone at 77°K 147 Thermolysis ir cell 147 Flash thermolysis of 4,5-dimethylenetropone 152 Attempted trapping of the labile product with N-phenyl maleimide 153 Attempted trapping of the labile product with 1,1-dimethoxyethylene 153 Reaction of 4,5-dimethylenetropone and N-phenyl maleimide 154 Irradiation of the Diels-Alder adduct at 77°K 155 Irradiation of the Diels-Alder adduct in methanol at -40° 155 BIBLIOGRAPHY 157 ACKNOWLEDGMENTS 165 V LIST OP FIGURES Page Figure 1. Infrared spectra 30 Top; Aminoketone (9-niethyl-9- azatricyclo[3.3.1.0® » ®]- nonan-3-one) Middle: Quaternary tosylate (9,9- dlmethyl-3-oxo-9-azonlatri- cydo[3.3.1.0®»®]nonane tosylate) Bottom: 4,5-Homotropone Figure 2. Nuclear magnetic resonance spectra 32 Top: Aminoketone (9-methyl-9- azatrlcyclo[3.3.1.0® » ®]- nonan-3-one) Bottom: Quaternary tosylate (9,9- dlmethyl-3-oxo-9-azoniatrl- cyclo[3.3.1.0®» ®]nonane tosylate) Figure 3. Nuclear magnetic resonance spectra 40 Top: 4,5-Homotropone Bottom: 4-Hydroxyhomotropylium cation Figure 4a. A plot of Ai versus of 46a 4,5-homotropone Figure 4b. A plot of ë. versus of 46c 4,5-homotropone Figure 5. Ultraviolet absorption spectra of 50 4,5-homotropone in various sulfuric acid solutions vi Page Figure 6. Infrared spectra 111 Top: Aminoketone (lO-methyl-10- azatricyclo[4.3.1.0^s®]- decan-8-one) Middle: Quaternary tosylate (10,10- dimethyl-8-oxo-lO-azoniatri- cyclo[4.3.1.0^'®]decane tosylate) Bottom: Bicyclo[5.2.0]nona-2,5-dien-4-one Figure 7. Nuclear magnetic resonance spectra 113 Top: Aminoketone (lO-methyl-10- az,àtricyclo[4.3.1. 0^ s ®]decan- 8-one) Middle: Quaternary tosylate (10,10- dimethyl-8-oxo-lO-azoniatri- cydo[4.3.1.0^' S]decane tosylate) Bottom: Bicyclo[5•2.0]nona-2,5-dien-4-one Figure 8. Infrared spectra 123 Top: 4,5-Dimethylenetropone Middle ; Diels-Alder adduct (4-phenyl-4- azatetracyclo[5.4.3.0^>® trideca-3,5,12-trioxo-lO,13-diene) Bottom; Propellane (inethyl-4-phenyl-4- azatetracyclo[7.2.1.0^»® 0^»^]- dodeca-3,5-dioxo-7-en-12-yl acetate) vil Page Figure 9- Nuclear magnetic resonance spectra 127 Top: 4,5-Dimethylenetropone Middle: Dlels-Alder adduct (4-phenyl-4- azatetracyclo[5. ^. 3-0^ > ® Cr,iO]_ trideca-3,5jl2-trloxo-10,13-dlene) Bottom: Propellane (methyl-4-phenyl-^- azatetracyclo[7.2.1.0^»® O^s®]- dodeca-3,5-dloxo-7-en-12-yl acetate) Figure 10. Infrared spectra 132 Top: 4,5-Dlmethylenetropone at 190° Middle: Pyrolysls product of 4,5- dlmethylenetropone at -190° Bottom: Pyrolysls product of 4,5- dlmethylenetropone after warming to 0° and recoollng to -190° Figure 11. Side view of thermolysis Infrared cell 149 Figure 12. Front view of thermolysis Infrared cell 151 vlii LIST OF SCHEMES Page Scheme 1. Mass fragmentation scheme for amlnoketone 35 (9-methyl-9-azatricyclo[3.3.1•0 ® ®]nonan- 3-one) Scheme 2. Mass fragmentation scheme for amlnoketone 116 (10-methyl-10-azatricyclo[4.3.1.0^ s ®]- decan-8-one) Ix QUOTATION There Is no short cut to a new thing. It must be preceded by long and tedious hours of experimentation and scores of disappointment. The only time you cannot afford to fall is the last time you try. Charles F. Kettering 1 PART I. SYNTHESIS AND REACTIONS OF 4,5-HOMOTROPONE 2 INTRODUCTION The term "aromatic" as applied to organic compounds was first used in the nineteenth century to describe compounds of aromatic odour isolated from natural oils. The terms 'aromatic' and 'benzenoid' were equated during this time when August Kekule proposed the well-known cyclic structure for benzene and suggested that the peculiar properties of the aromatic compounds are dependent on the properties of this ring system.
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