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An Exploration of the C9H8O Energy Surface in the Vicinity of Bicyclo[5.2.0]Nona-2,5,8-Trien-4-One David Michael Lokensgard Iowa State University

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An Exploration of the C9H8O Energy Surface in the Vicinity of Bicyclo[5.2.0]Nona-2,5,8-Trien-4-One David Michael Lokensgard Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1978 An exploration of the C9H8O energy surface in the vicinity of bicyclo[5.2.0]nona-2,5,8-trien-4-one David Michael Lokensgard Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Lokensgard, David Michael, "An exploration of the C9H8O energy surface in the vicinity of bicyclo[5.2.0]nona-2,5,8-trien-4-one " (1978). Retrospective Theses and Dissertations. 6465. https://lib.dr.iastate.edu/rtd/6465 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. 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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. University Microfilms International 300 North Zeeb Road Ann Arbor, Michigan 48106 USA St. John's Road. Tyler's Green High Wycombe, Bucks. England HP10 8HR 7613236 L0KE%SGAR0, DAVID ^ICH^EL AN EXPLORATION OF i,2.BE%Z0PYHAN ENERGY SURFACE IN THE VICINITY OF BICYCL0(5,2,0)N0NA.2,S,8"TRIEN.4.0NE, IO*A STATE UNIVERSITY, PH.D., 1975 UniversiN Microfilms Internationa] soon, zeeb road, ann arbor, mi «siœ An exploration of the CgHgO energy surface in the vicinity of bicyclo[5.2.0]nona-2,5,8-trien-4-one by David Michael Lokensgard A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Department: Chemistry Major: Organic Chemistry Approved: Signature was redacted for privacy. Ih^Charge of Ma^or Work Signature was redacted for privacy. For the Mador 'Deéèrtment Signature was redacted for privacy. For tne Graduate college Iowa State University Ames, Iowa 1973 ii TABLE OF CONTENTS Page INTRODUCTION 1 LITERATURE REVIEW 6 Homoconjugation and its Incorporation into the 6 Tropyliuni System The Rearrangements of Bicyclo[6.1.0]nona-2,4,6- 25 triene and its Derivatives The Effects of Structural and Electronic Modification 74 on the Reactivity of the Bicyclo[6.1.0]nonatriene System RESULTS AND DISCUSSION 99 The Synthesis of Bicyclo[5.2.0]nona-2,5,8-trien-4-one 99 The Aqueous Thermal Rearrangement of Bicyclo[5.2.0]- 129 nona-2,5,8-tri en-4-one The Non-Aqueous Thermal Rearrangement of Bicyclo- 137 [5.2.0]nona-2,5,8-trien-4-one The Nature of the 4-Hydroxybicyclo[5.2.0]nona-2,5,8- 158 trien-4-ylium Cation An Attempt to Prepare a Bishomoaromatic Radical Anion 168 4,5-Bis(methylene)cyclohepta-2,6-dien-l-one, a £- 175 Tropoquinone Dimethide i i i EXPERIMENTAL 192 General 192 Preparation of trans-7,8-dibromobicyclo["4.2.0] - 193 octa-2,4-diene Preparation of trans-6,7-dibromo-(cis,exo,- and 194 trans-)2,4-diethoxy-3-oxabicyclo[3.2.0]heptane (I) Preparation of cis,exo- and trans-2,4-diethoxy-3-oxa- 197 bicyclo[3.2-0]hept-6-enes (II) Preparation of cis,exo- and trans-2,4-diethoxy-3-oxa- 199 bicycl0[3.2.0]heptanes (XII) 2 5 Preparation of 10-methyl-10-azatricyclo[4.3.1.0 ]- 199 dec-3-en-8-one (III) Preparation of 10-methyl-10-azatricyclo[4.3.1.0 ' ]- 201 decan-S-one (XIII) Preparation of 10-methyl-7,7,9,9-tetradeutero-lO-aza- 201 2 5 tricyclo[4.3.1.0 ' ]dec-3-en-8-one (Illd) Preparation of 10,10-dimethyl-10-azoniatricyclo- 202 2 5 [4.3.1.0 ' ]dec-3-en-8-one £-toluenesulfonate (IV) Preparation of 10,10-dimethyl-7,7,9,9-tetradeutero- 203 2 5 10-azoniatricyclo[4.3.1.0 ' ]dec-3-en-8-one tosylate (IVd) Preparation of 10,10-dimethyl-10-azoniatricyclo- 203 [4.3.1.0 ' ]decan-8-one tosylate (XIV) Preparation of 2,6-bis(trimethylammonio)bicyclo[5.2.0]- 203 non-8-en-4-one diiodide (VII) iv Preparation of 2,6-bis(trimethylammonio)-4-oxabicyclo- 204 [5.2.0]nonane diiodide (XV) Attempted preparation of bicyclo[5.2.0]nona-2,5,8-trien- 204 4-one (VI) by steam distillation from base of 2 5 10,lO-dimethyl-lO-azoniatricyclo[4.3.1.0 ' Jdec-3- en-8-one tosylate (IV); isolation of bicyclo[4.2.1]- nona-2,4,7-trien-9-one (V) Preparation of bicyclo[5,2.0]nona-2,5,8-trien-4-one (VI) 205 Preparation of bicyclo[5.2.0]nona-2,5-dien-4-one (XVI) 207 Determination of the effects of solvent polarity and 208 water on the course of thermal rearrangement of bicyclo- [5.2.0]nona-2,5,8-trien-4-one (VI) Preparation of 3,5-dideuterobicyclo[5.2.0]nona-2,5,8- 208 trien-4-one (VId), and its rearrangement in aqueous media N.m.r. observation of the non-aqueous thermal rearrangement 210 of bicyclo[5.2.0]nona-2,5,8-trien-4-one (VI) N.m.r. observation of the non-aqueous thermal rearrangement 211 of 3,5-dideuterobicyclo[5.2.0jnona-2,5,8-trien-4-one (VId) Attempted isolation and trapping of intermediate IX 212 Attempted isolation of intermediate X 212 Procedure for the preparation of samples of protonated 213 ketones at low temperatures for n.m.r. observation N.m.r. observation of protonated bicyclo[5.2.0]nona-2,5,8- 215 trien-4-one (XI) V N.m.r. observation of protonated bicyclo[5.2.0]nona-2,5- 215 dien-4-one (XVII) Generation of a radical anion from bicyclo[5.2.0]nona- 216 2,5,8-trien-4-one (VI) Preparation of bicyclo[5.2.0]nona-l(7),2,5-trien-4- 216 one (XVIII) Generation and observation of a radical anion from 217 bicycl0[5.2.0]nona-1(7),2,5-trien-4-one (XVIII) Preparation of 4,5-bis(methylene)cyclohepta-2,6-dien- 218 1-one (XIX), and observation of its spectra and photo­ chemistry at 8K in an argon matrix Attempted trapping of the reactive intermediate produced 219 byf1ash thermolysis of bicyclo[5.2.0]nona-l(7),2,5- trien-4-one (XVIII), and isolation of a dimer of 4,5-bi s(methylene)cyclohepta-2,6-di en-l-one Infrared observation of the non-aqueous rearrangement of 221 bi cycl0[5.2.0]nona-2,5,8-tri en-4-one (VI) BIBLIOGRAPHY 223 ACKNOWLEDGEMENTS 238 vi LIST OF FIGURES Figure 1. Nuclear Magnetic Resonance Spectra (CDCI3, 60 MHz) 104 Top: trans-6,7-Dibromo-cis,exo-2,4-diethoxy-3-oxa- bicyclo[3.2,0]heptane (Ic) Bottom: endo-6-exo-7-Dibromo-endo-2-exo-4-diethoxy-3- oxabicyclo[3.2.0]heptane (It) Figure 2, Nuclear Magnetic Resonance Spectra (CDCI3, 60 MHz) 108 Top: cis,exo-2,4- Diethoxy-3-oxabicyclo [3.2.0]hept- 6-ene (lie) Bottom: trans-2,4- Diethoxy-3-oxabi cycl 0 [3.2.0]hept-5-ené (lit) Figure 3. 10-Methyl-10-azabicycl0 [4.3.1.0^'^]dec-3-en-8- 112 one (III) Top: Nuclear magnetic resonance spectrum (CDCI3, 60 MHz) Bottom: Infrared spectrum (KBr) Figure 4. Bicycl0[5.2.0]nona-2,5,8-trien-4-one (VI) 121 Top: Nuclear magnetic resonance spectrum (CCI4, 100 MHz) Bottom: Infrared spectrum (neat) Figure 5. Nuclear Magnetic Resonance Spectra (CDCI3, 100 MHz) 134 Top: Bi cycl0[4.2.1]nona-2,4,7-tri en-9-one (V) Bottom: 1,2-Dideuterobicycl0[4.2.1]nona-2,4,7-trien-9-one (Vd) Figure 6.
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