DOCSLIB.ORG

Octa-3,5-Diene

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Octa-3,5-Diene 4494 J. Am. Chem. Soc. 1981, 104, 4494-4496 of the 2Hj1H ratios is by complete combustion of the organic resonance lines to specific molecular sites was accomplished from matter to C02 and H20 and rcduction to H 2 in a uranium fumace analysis of the corresponding 500-MHz proton spectra or from and mass spcctroscopic analysis of the isotropic ratio of the whole associating the protons with a specific carbon peak by using compound without any indication of isotopic ratios as a function selective proton decoupling. of site within the molecule. Some effort has been made to be more selective in analysis of 2Hj1H ratios. In particular, work has been Acknowledgment. This work was supported in part by the done on tbe nonexchangable hydrogens of cellulose."J While these National Institutes of Health under Grant GM 08521 from the studies focused on one type of sitc by eliminating the hydroxyl Institute of General Medical Sciences. Spectra were obtained hydrogens, the 2Hj1H ratios were not site specific for the C-H at the Southern California Regional NMR Facility, supported hydrogens. Rauschenbach et al.6 compared 2H/1H ratios for by the National Science Foundation on Grant CHE 79-16324. synthetic and fennented ethanols and also detcnnined the isotopic Reaistry No. Methylcyclohexane, 108-87-2; 1,1 ,3-trimethylcyclo­ ratio in the mcthyl group of the ethanol by oxidation to acetic hexane, 3073-66-3; d-camphor, 464-49-3. acid and analysis of the corresponding acetate salt. Martin and Martin7•8 recently have used 2H NMR to show that the isotopic distribution of 2H in ethyl and vinyl groups varies from molecule to molecule. The full significance of observing site-specific isotopic effects Tricyclo[ S.l.O.Ol.l]octa-3,5-diene ( Octavalene) upon the 2Hj1H ratio is emphasized when it is realized that such information is not readily available from the traditional mass Manfred Christi* and Reinhard Lang spectrometric methods of measuring isotope ratios. Although mass spectral methods are much more sensitive than NMR techniques Institut für Organische Chemie and have a much larger dynamic rangc, such methods can only der Universität Würzburg, Am Hubland measure the averagc molecule 2H/1H isotope ratio because of the D-8700 Würzburg, Federal Republic of Germany 1 2 facile scrambling of the molecular hydrogens (both H and H) Received April 22, 1982 in the typical mass spectrometric ion. Futhennore, these hydrogen 5 rearrangements can be isotopic selectivities as large as 10 in somc 1 9 The unique properties of the (CH)8 hydrocarbons have at­ instanccs. Such large isotope effects would completely mask tracted the attention of many organic chemists. As a member thc significant but still smaller intramolecular ratios that we have of this series the title compound (8) enjoys special interest. Tbc been recently observing. Thus, high-field deuterium magnetic 2 butadiene bridge should substantially widen the dihedral angle resonance, H NMR, techniques provide a unique method for of the bicyclo[ 1.1.0] butane system from the normal value of about detcrmining this potentially valuable information. 122 o, 2 resulting in an increased strain energy. T~is, as weil as Site-specific isotopic ratios have the potential for more complete the electronic interaction of the 'II" system and the stramed " system, characterization of the rate-controlling processes in rather complex Ieads one to anticipate that 8 will exhibit unusual chemical and chemical and biosynthesis processes. Detailed information on 2 1 spectroscopic properties. Furthermore, the Woodward-Hoffmann mechanistic steps should be available from variations in the H/ H rules allow a thermally induced [1,5] carbon shift. Repetition ratio as a function of molecular site. This technique, applicable of this degenerate rearrangement would finally equilibrate all CH at natural abundance, allows analysis without destruction of the groups. Thus, 8 could be te bullvalene equivalent of the (CH)s sample and removes the possibility of artifical inhibition of a family. metabolic system by excess deuterium present in Iabel~ ~om­ Interested in such prospects, several research groups have un­ pounds. Finally, as found in our two camphors, one may anttCJpate dertaken to synthesize 8. When 8,8-dibromobicyclo[S.l.O]octa- the opportunity of observ!ng the chemical history of !w~ ide~tical 2 4-diene was treated with methyllithium, the resulting carbene molecules derived from dtfferent precursors from vanattons m the 3 4 2 1 r~rranged to a dihydropentalene • instead of inserting into the intramolecular Hf H ratios stampled into the molecule by al­ syn-6-CH bondas intended. Likewise, the tricarbonyl iron com­ ternative synthetic pathways. With improved sensitivity and 2 plex of the dibromide with methyllithium failed ~o give the desired spectral dispersion at very high fields, proton-decoupled H NMR 5 1 insertion product. In analogy to the preparatton of benzvalene can now realize its full potential. The significant isotope effects 6 2 via cyclopentadienylcarbene the intramolecular [~ + 1] or [6 + observed herein further enhance the importance of H NMR 1) cycloaddition of cycloheptatrienylcarbene to gtve 8 has been techniques. 2 attempted. However, only cyclooctatetraene, heptafulvene, Experimental Section. Tbc 76.77-MHz H spectra were re­ benzene, and acetylene could be identified as reaction products.' corded on a Bruker WM500 spectrometer operating in Fourier Also, the disrotatory opening of the cyclobutene portion in tet­ transform mode. Methylcyclohexanc and 1,1,3-trimethylcyclo­ racyclo[ 4.2.0.02•4.03.s]oct-7-ene, which shoul~ produce 8, could hexane were run as neat liquids, and d-camphor was prepared as not be achieved without rearrangement of the btcyclo[l.l.O]butane a nearly saturated solution in chloroform. Each sample contained system.8 In addition, a Straightforward route to prepare ~­ 1O% tetramethylsilane as a chemical shift reference. Spectra bromooctavalene by cyclopropane ring enlargement of the dt­ requiring about 400 scans were acquired at 8-s intervals by utilizing bromocarbene adduct of homobenzvalene and subsequent hy­ a 90° pulse and a 2-s data aquisition of 2048 points. Broad-band drogen bromide elimination failed because under all conditions decoupling at 5 W of power was used with the power reduced to tried a trans-bis(homobenzene) derivative was formed in the first 0.4 W during the interval between accumulations to allow the step,9· 10 most probably in an acid-catalyzed process. 10 Here, we nuclear magnetization of the sample to recover under redu~ed dielectric heating. Free induction decays were filtered by usmg a Lorentzian to Gaussian line-shape transformation and zero ftlled (1) Smith, L. R. J. Chem. Educ. 1978, 55, 569-510 and Iiterature cited to 8192 points before Fourier transformation. Assignment of ~~ . (2) Cox, K. W.; Harmony, M. 0.; Nelson, G.; Waberg, K. 8. J. Chem. Phys. 1969, 50, 1976-1980. (3) Smitb, B. N.; Jacoblen, B. S. plant Cell PhyJtol. 19'76, 17, 1089-1092. (3) Van Vuurcn, P. J. Ph.O. Thesis Cornell Univenity, Ithaca, NY, 1970; (4) Epstcin, S.; Yapp, 0. J.; Hall, J. N. Earth Planet Sei. Lm. 1976, 30, Diss. Abstr. B 1971, 31B, 7201. 241-251. (4) Baird, M. S.; Reese, C. 8. Tetrahedron Lett. 1976, 2895-2898. (5) Epstcin, S.; Tbornaon, P.; Yapp, C. J. Science (Washington, D.C.) (5) Van Vuuren, P. J.; Fletterick, R. J.; Mcinwald, J.; Hughes, R. E. J. 1977, 198, 1209-1215. Am. Chem. Soc. 1971, 93, 4394-4399. (6) RaUJChenbach, P.; Simon, H.; Stichler, W.; Maser, H. Z. Naturforsch, (6) Katz, T. J.; Wang, E. J.; Acton, N. J. Am. Chem. Soc. 1971, 93, C 1979, 34C, 1-4. 3782-3783. (7) Marti.n, G. J.; Martin, M. L. Telrahedran Lett. 1981, 22, 3525-3528. (7) Zimmerman, H. E.; Sousa, L. R. J. Am. Chem. Soc. 1972, 94, (8) Martin, G. J.; Martin, M. L. Compt. Rend. Acad. Sei., Ser. 1/1981, 834-842. 293, 31-33. (8) Smith, L. R.; Gream, G. E.; Meinwald, J. J. Org. Chem. 1977, 42, (9) Futrell, J. H., private consultation. 927-936. 0002-7863/82/1504-4494$01.25/0 <e> 1982 American Chemical Society Communications to the Editor J. Am. Chem. Soc., Vol. 104, No. 16, 1982 4495 19 22 Scheme I the tribromides 419·21 and 5 · in a ratio of 2:1, from which 4 Br was isolated in 54% yield as a crystalline solid after treatment with methanol. On the basis of the size of the coupling constants ~~H+ in bridged cyclobutanes23 the stereochemistry of C-7 and C-8 in 4 and 5 follows unambiguously from the 1H NMR spectra. &;Y Although mechanistic investigations have not been carried out, 2 3 the stereochemical outcome appears to support a radical pathway for the bromination of 1 and 3. We assume that a bromine atom is added to C-3 from the sterically less bindered side with inversion, parallel with the reaction between thiophenol and bicyclo­ [I.l.O]butane derivatives. 24 The resulting cyclobutyl radicat may eH Br accept the second bromine atom in principle from both sides. Starting from 2, however, the endo-bromine atom at the cyclo­ 1 c propane ring interferes, thus allowing only the formation of 4. The H 6 SJ+-- Jj7 H ~ L-----I- cyclobutyl radicat originating from 3 experiences tess steric hin­ Br drance because the cyclopropane ring carries its bromine sub­ 4 stituent in the exo position. Then the second bromine enters to produce the cis-dibrominated cyclobutane derivative 5 in accord with the preferred stereochemical course in halogenations of bicyclo[ 1.1.0] butadiene derivatives.ll·13·15 For well-known stereoelectronic reasons, 4 thermolyzed smoothly to the ring-enlarged tribromide 619·25 (81% yield) at 100 °C in acetonitrile, while 5 decomposed above 1SO °C to un­ identified products.
Load more

Recommended publications
  • Xarox University Microfilms
    INFORMATION TO USERS Thil material was produced from a microfilm copy of the original documant. While the moat advanced technological meant to photograph and reproduce this documant have been used, the quality is heavily dependant upon the quality of the original submitted. The following explanation o f techniques is provided to help you understand markings or patterns which m ay appear on this reproduction. 1. The sign or "target" for pages apparently lacking from the document photographed is "Misting Page(s)". If it was possible to obtain the misting page(s) or section, th a y era spliced into the film along with adjacent pages. This may have necessitated cutting thru an image and duplicating adjacent pagae to insure you complete continuity. 2. Whan an image on th e 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 causa a blurred image. You will find a good image of the pnga in the adjacent frame. 3. Whan a map, drawing or chart, etc., was part of the material being photographed the photographer followed a definite method in "sectioning" the material. It ie customary to begin photoing at the upper left hand comer 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 end 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.
    [Show full text]
  • 37Th Rocky Mountain Conference on Analytical Chemistry
    Rocky Mountain Conference on Magnetic Resonance Volume 37 37th Rocky Mountain Conference on Article 1 Analytical Chemistry July 1995 37th Rocky Mountain Conference on Analytical Chemistry Follow this and additional works at: https://digitalcommons.du.edu/rockychem Part of the Chemistry Commons, Materials Science and Engineering Commons, and the Physics Commons Recommended Citation (1995) "37th Rocky Mountain Conference on Analytical Chemistry," Rocky Mountain Conference on Magnetic Resonance: Vol. 37 , Article 1. Available at: https://digitalcommons.du.edu/rockychem/vol37/iss1/1 This work is licensed under a Creative Commons Attribution 4.0 License. This Article is brought to you for free and open access by Digital Commons @ DU. It has been accepted for inclusion in Rocky Mountain Conference on Magnetic Resonance by an authorized editor of Digital Commons @ DU. For more information, please contact [email protected],dig- [email protected]. et al.: 37th RMCAC Final Program and Abstracts 37TH ROCKY MOUNTAIN CONFERENCE ON ANALYTICAL CHEMISTRY FINAL PROGRAM AND ABSTRACTS JULY 23-27, 1995 HYATT REGENCY DENVER 1750 WELTON STREET DENVER, COLORADO SPONSORED BY: ROCKY MOUNTAIN SECTION SOCIETY FOR APPLIED SPECTROSCOPY & COLORADO SECTION AMERICAN CHEMICAL SOCIETY Published by Digital Commons @ DU, 1995 1 Rocky Mountain Conference on Magnetic Resonance, Vol. 37 [1995], Art. 1 TABLE OF CONTENTS Conference Organizers 2 Symposia Organizers 3 Registration and Event Information 5 Exhibitor List 8 Hotel and Visitor Information 9 Employment Clearing House and Professional Memberships 9 Short Courses 10 Vendor Workshops 12 Symposia Schedule: Atomic Spectroscopy 17 Chromatography 18 Compost (Biogeochemistry of) 19 Electrochemistry 20 Environmental Chemistry 22 EPR 25 FTIR/NIR/RAMAN Spectroscopy 37 General Posters 37 ICP-MS 39 Laboratory Safety 41 Luminescence 42 Mass Spectrometry 44 NMR 47 Pharmaceutical Analysis 59 Quality Assurance 60 Downtown Denver Street Map Inside back cover Abstracts start after page 61.
    [Show full text]
  • 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.
    [Show full text]
  • 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 Bell & Howell Information Company 300 North ZeebRoad Ann Arbor Ml 48106-1346 USA 313/761-4700 800 521-0600 Order Number 9427071 The chemistry of polycyclic and spirocyclic compounds Branan, Bruce Monroe, Ph.D. The Ohio State University, 1994 UMI 300 N.ZeebRd. Ann Arbor, MI 48106 THE CHEMISTRY OF POLYCYCLIC AND SPIROCYCLIC COMPOUNDS DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University by Bruce Monroe Branan ***** The Ohio State University 1994 Dissertation Committee: Approved by Professor Leo A.
    [Show full text]
  • The Synthesis of Carbacyclic Silanes Via Organosilicon Reactive Intermediates Michael J
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1984 The synthesis of carbacyclic silanes via organosilicon reactive intermediates Michael J. Vuper Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Vuper, Michael J., "The synthesis of carbacyclic silanes via organosilicon reactive intermediates " (1984). Retrospective Theses and Dissertations. 7737. https://lib.dr.iastate.edu/rtd/7737 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]. INFORMATION TO USERS Tliis 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.
    [Show full text]
  • William Von Eggers Doering's Remarkable Career - Personal Observations from the 1950S and '60S
    William von Eggers Doering's Remarkable Career - Personal Observations from the 1950s and '60s "... the questions themselves" Rainer Maria Rilke RONALD M. MAGID AND MAITLAND JONES, JR. Department of Chemistry, The University of Tennessee; Department of Chemistry, New York University Received Dedicated to Professor Bill Doering on the occasion of his 90th birthday ______________________________________________________________ ABSTRACT This Account consists of reminiscences about the Doering research group at Yale University, nearly a half-century ago. We recount vignettes and events that reflect the state of research in physical organic chemistry at that early time, the passion that drove Doering, and the lessons that he taught to his coworkers. We allude to specific research results that are described in considerable detail in the preceding article. _________________________________________________________________ In the accompanying article1 we describe some of the truly remarkable research accomplishments by Bill Doering and his coworkers over a 60-year-span. An editor, who may yet regret it, thought that it would be interesting to include some reminiscences by two of Bill's former graduate students. It was suggested that they might focus on the human side of the equation: what made Doering tick, how did the research group function, what was the nature of physical organic chemistry research and equipment in the 1950s-60s, etc. RMM and MJJr are the co-authors of this Account. Both were Yale undergraduates in Bill's introductory organic course in Spring-Fall, 1957, and both did their graduate work under Bill's supervision. MJJr's knowledge of Doering both precedes and supercedes the 1957-1963 period. Even before college, he had spent some summers at Hickrill Chemical Research Laboratory (about which much more, soon).
    [Show full text]
  • Organic Chemistry Masterclasses
    Organic Chemistry Masterclasses By S. Ranganathan All rights reserved. No parts of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopy- ing, recording, or otherwise, without prior permission of the publisher. © Indian Academy of Sciences Published by Indian Academy of Sciences 2 Foreword The Masterclass series of eBooks published by the Indian Academy of Sciences, Bengaluru brings together pedagogical articles on single broad topics reproduced from Resonance, Journal of Science Education that is published monthly by the Academy since January 1996. Primarily directed at students and teachers at the undergraduate level, the journal has brought out a wide spectrum of articles in a range of scientific disciplines. Articles in the journal are written in a style that makes them appealing to readers from diverse backgrounds, and in addition, they provide a useful source of instruction that is not always available in textbooks. It is fitting that the first book in this series,Organic Chemistry Masterclasses, is by a legendary teacher, Professor Subramania Ranganathan, highly acclaimed and distinguished Organic Chemist. Ranga, as he is fondly known to generations of students at the IIT Kanpur where he taught for over three decades, has been a regular contributor to Resonance and his articles enjoy wide popularity among the journal’s readership. Indeed his first contribution toResonance was in the very first issue of the journal. We are also delighted that this collection of over fifteen articles, reformatted as an eBook will mark his 80th birthday. Those of us who were fortunate to have learned some of these topics as he was devising ways of teaching them will be very pleased that some of Ranga’s masterly instructions can reach a much wider audience through this means.
    [Show full text]
  • Noncovalent Control of Β-Cyclodextrin Over Shapeshifting Molecules
    Durham E-Theses Noncovalent Control of β-Cyclodextrin over Shapeshifting Molecules WEN, YUZHEN How to cite: WEN, YUZHEN (2020) Noncovalent Control of β-Cyclodextrin over Shapeshifting Molecules, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/13717/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk Noncovalent Control of β-Cyclodextrin over Shapeshifting Molecules Yuzhen Wen A Thesis Submitted for the Degree of Master by Research August 2020 Table of Contents Abstract..................................................................................................................................... i Acknowledgements................................................................................................................ ii Abbreviations........................................................................................................................
    [Show full text]
  • Jones Isomers”
    BIOSYNTHETIC STUDIES OF OTTELIONE A AND THE STRUCTURAL RE-ANALYSIS OF THE “JONES ISOMERS” THE STRUCTURAL REASSIGNMENT OF PHOMOPSICHALASIN TO THAT OF DIAPORTHICHALASIN A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA By Susan G. Brown IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Thomas R. Hoye, Adviser February 2013 © Susan G. Brown 2013 Portions © J. Nat. Prod. 2012 and used with permission i ACKNOWLEDGEMENTS Firstly I would like to thank my adviser professor Thomas Hoye for his patience, guidance and mentorship throughout my time spent in his group. His keen ability to hone in on the details of the problem at hand has made me into the chemist that I am today. To professors Andrew Harned, Wayland Noland and Robert Fecik, thank you for serving as members on my committee as well as for the helpful conversations along the way. I would also like to thank my undergraduate adviser, professor Rebecca Hoye. Becky, your mentorship and willingness to always serve as a listening ear was truly indispensable both throughout my time at Macalester and the University of Minnesota. To my friends from the “consulate”, thank you for making Minnesota my home away from home for the past several years. Finally to my mother and father, Dothlyn and Albert, your unwavering love and support has enabled the completion of this thesis. Thank you for being devoted parents. ii DEDICATION To my mother and father, Dothlyn and Albert Brown. iii ABSTRACT Part I Ottelione A, isolated from the fresh water plant Ottelia alismoides, is a cytotoxic agent at nanomolar levels against 60 human cancer cell lines.
    [Show full text]
  • Copyrighted Material
    JWST960-SUBIND JWST960-Smith October 25, 2019 9:5 Printer Name: Trim: 254mm × 178mm SUBJECT INDEX The vast use of transition metal catalysts in organic chemistry makes the citation of every individual metal impractical, so there are limited citations of individual metals. Palladium is one exception where individual citations are common, in keeping with the widespread use of that metal. However, in most cases, the term metal catalyst, or catalyst, metal is used as a heading, usually representing transition metals. A-SE2 mechanism 893 and the steering wheel model acceleration of Diels-Alder reactions 487 151–152 reactions, high pressure A1 mechanism, acetal hydrolysis and universal NMR database 1038 487 155 hydrogen-bonding 1038 A1,3-strain 196 Cahn-Ingold-Prelog system hydrophobic effect 1038 A2 mechanism, acetal hydrolysis 149–152 in water 1038 487 determination 152 ionic liquids 1038 ab initio calculations 36 D/L nomenclature 149 micellular effects 1038 and acidity 346 Kishi’s NMR method 155 microwave irradiation 1038 and antiaromaticity 71 sequence rules 149–152 phosphate 1039 and nonclassical carbocations absolute hardness 64, 359, 361 solid state 1038 427 table 361 ultracentrifuge 1038 norbornyl carbocation 436 absorbents, chiral 168 ultrasound 1038 ab initio studies 248 absorption, and conjugation 317 zeolites 1038 1,2-alkyl shifts in alkyne anions differential, and diastereomers acceleration, Petasis reaction 1349 168 1202 and cubyl carbocation 413 differential, and resolution 169 acenaphthylene, reaction with and SN2 408–409 abstraction,
    [Show full text]
  • Empowering Women in Organic Chemistry 2021
    Empowering Women in Organic Chemistry 2021 Poster Abstract Booklet Abstracts listed alphabetically by last name Poster Session 1: 4:00–5:00pm EDT, June 24, 2021 Poster Session 2: 5:00–6:00pm EDT, June 24, 2021 Information for Attendees Each poster will have an assigned Zoom room by session. Session assignments are indicated at the top of each abstract page in this booklet. Links to access the rooms will be provided to registrants via the conference landing page https://meetingtomorrow.com/event/ewoc2021/ or directly at https://meetingtomorrow.com/ event/ewoc2021/poster-sessions. These pages are password-protected. The password will be provided to registered atteendees by email a few days in advance of the conference. Select the room link(s) to visit the poster(s) of interest to you. You may come and go from the poster rooms as you please. In this virtual poster session format, we have encouraged presenters to use whatever format works best to present their work; in some cases, presenters may use several slides instead of the traditional static poster. **Do not photograph or record the poster presentations unless you have the explicit permission of the presenter. ABRAHAM Characterizing Release of Small Molecule Cargo from Phenylalanine- Derived Supramolecular Hydrogels Brittany L. Abraham, Ethan S. Toriki, N’Dea J. Tucker, and Bradley L. Nilsson* Department of Chemistry, University of Rochester, Rochester, NY 14627-0216, USA. [email protected] Supramolecular hydrogels, formed by the self-assembly of molecules into nanostructures that entangle in water to form a three-dimensional network, have shown promise as biomaterials for sustained drug delivery.
    [Show full text]
  • Chemistry of Allyl Nitrate Esters, Β-Nitroacetamides, and Various Other
    Chemistry of Allyl Nitrate Esters, β-Nitroacetamides, and Various Other Nitro Compounds A Thesis Submitted to the Faculty Of Drexel University By Nicholas Paparoidamis in partial fulfillment of the requirements for the degree of Doctor of Philosophy November 2013 © Copyright 2013 Nicholas Paparoidamis. All Rights Reserved. ii Acknowledgements I would like to thank Professor Peter Wade for his mentorship and all the other professors and staff who supported me: Dr. Robert Hutchins, Dr. Anthony Addison, Dr. Yen Wei, Dr. Teck-Kah Lim, Dr. David Ruth, Mr. Steve Leesman, Mr. Tim Wade, Mr. Edward Doherty, and so many others. Thank you to every one of my colleagues at Drexel University for their comradeship and support, especially Dr. April Holcomb, Dr. Jonathan Haulenbeek, LT Dr. Christopher Castillo, Arben Kojtari, Noah Johnson, Joshua Smith, and Panagiota Tsetsakos. I would like to most importantly thank my family, Tom Paparoidamis, Fotini Paparoidamis, and Georgia Paparoidamis for all their support during my studies. iii Table of Contents LIST OF TABLES v LIST OF FIGURES vi ABSTRACT vii CHAPTER 1: Tandem Nitration / Rearrangement of Allylic Alcohols 1.1 Introduction 1 1.2 Results and Discussion 22 1.3 Structure Assignments 29 1.4 Experimental 33 1.5 Conclusions 43 CHAPTER 2: Synthesis and Reactions of β-Nitroacetamides 2.1 Introduction 45 2.2 Results and Discussion 52 2.3 Structure Assignments 77 2.4 Experimental 102 2.5 Conclusions 146 CHAPTER 3: Debromination of 2,4-Dibromo-2,4-dinitropentane 3.1 Introduction 148 3.2 Results and Discussion 153 3.3 Structure Assignments 156 3.4 Experimental 157 iv Table of Contents (continued) 3.5 Conclusions 159 LIST OF REFERENCES 160 APPENDIX A: 1H NMR SPECTRA 164 APPENDIX B: 13C NMR SPECTRA 200 VITA 236 v List of Tables 1.
    [Show full text]