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2004 DOE/BES Analysis Program Contractors' Meeting
2004 DOE/BES Analysis Program Contractors’ Meeting Annapolis, Maryland February 12 – 14, 2004 Sponsored by The U.S. Department of Energy Office of Basic Energy Sciences Workshop Chair: John Miller 2004 DOE/BES Analysis Program Contractors’ Meeting Program and Abstracts Department of Energy Office of Science Office of Basic Energy Sciences Chemical Sciences, Geosciences and Biosciences Division FOREWORD This abstract booklet provides a record of the 2004 U.S. Department of Energy, Office of Basic Energy Sciences, Analysis Program Contractors’ Meeting. This group of scientists last met as part of the larger Separations and Analysis Program Contractors’ Meeting held in San Diego April 5-7, 2001. The agenda and abstracts of that meeting may be found on the web at http://www.sc.doe.gov/bes/chm/Publications/publications.html. There is wide agreement that a gathering of researchers with common interests and sponsorship provides a fruitful environment for exchange of research results, research techniques, and research opportunities. The primary means of communicating research achievements and perspectives at this meeting is oral presentations, formal discussion periods and informal breaks and meals. The agenda has been organized so that papers in related disciplines – such as mass spectrometry or optical spectroscopy – are loosely clustered together. I am pleased to have the privilege of organizing this meeting and of serving as the program manager of this world-class research program. In carrying out these tasks, I learn from the achievements, and share the excitement, of the research of the many sponsored scientists and students whose names appear on the papers in the following pages. -
Synthetic Applications of Dienes and Polyenes, Excluding Cycloadditions
The Chemistry of Dienes and Polyenes. Volume 2 Edited by Zvi Rappoport Copyright 2000 John Wiley & Sons, Ltd. ISBN: 0-471-72054-2 CHAPTER 9 Synthetic applications of dienes and polyenes, excluding cycloadditions NANETTE WACHTER-JURCSAK Department of Chemistry, Biochemistry and Natural Science, Hofstra University, Hempstead, New York 11549-1090, USA Fax: (516) 463-6394; e-mail: [email protected] and KIMBERLY A. CONLON Department of Pharmacological Sciences, School of Medicine, State University of New York at Stony Brook, Stony Brook, New York 11794-8651, USA Fax: (516) 444-3218; e-mail: [email protected] I. INTRODUCTION ..................................... 693 II. ADDITION REACTIONS ............................... 694 III. OXIDATION REACTIONS ............................... 700 IV. COUPLING REACTIONS ............................... 710 A. Wittig Reactions of Dienes and Polyenes .................... 711 B. Coupling Promoted by Organometallic Reagents ............... 712 V. DIMERIZATION REACTIONS ............................ 718 VI. PREPARATION OF METAL–POLYENE COMPLEXES ........... 720 VII. REARRANGEMENTS .................................. 722 A. Cope Rearrangement ................................. 722 B. Claisen Rearrangement ............................... 728 VIII. REFERENCES ....................................... 736 I. INTRODUCTION The reactivity of polyenes is influenced by their substituents, and whether or not the multiple double bonds of the unsaturated hydrocarbon are conjugated or isolated from 693 694 Nanette Wachter-Jurcsak and Kimberly A. Conlon one another. The -system of a polyene may be fully conjugated, or there may be one or more pairs of conjugated double bonds isolated from the other -bonds in the molecule, or, alternatively, each of the carbon–carbon double bonds in the polyene may be isolated from one another. Conjugated -systems react differently with electrophiles than isolated double bonds. Addition of hydrogen to isolated double bonds has been previously discussed in this series and will not be addressed here1. -
(12) United States Patent (10) Patent No.: US 9,072,293 B2 Yo0 Et Al
US009072293B2 (12) United States Patent (10) Patent No.: US 9,072,293 B2 Yo0 et al. (45) Date of Patent: Jul. 7, 2015 (54) CYCLOPROPENES AND METHOD FOR 6,452,060 B2 9, 2002 Jacobson APPLYING CYCLOPROPENESTO 6,548.448 B2 4/2003 Kostansek 6,762,153 B2 7/2004 Kostansek et al. AGRICULTURAL PRODUCTS OR CROPS 6,953,540 B2 10/2005 Chong et al. 2001/OO 19995 A1 9, 2001 Sisler (75) Inventors: Sang-Ku Yoo, Gyeonggi-do (KR); Jin 2004/00775O2 A1* 4/2004 Jacobson et al. .............. 504,313 Wook Chung, Seoul (KR) 2004/O192554 A1 9/2004 Kashimura et al. 2005/0065033 A1 3/2005 Jacobson et al. .............. 504,343 (73) Assignee: Erum Biotechnologies Inc., 2008/0286426 A1* 11/2008 Yoo ............................... 426,321 Gyeonggi-Do (KR) FOREIGN PATENT DOCUMENTS (*) Notice: Subject to any disclaimer, the term of this JP 10-94741 4f1998 patent is extended or adjusted under 35 KR 10-2003-0O86982 11, 2003 U.S.C. 154(b) by 0 days. KR 102003OO86982. A * 11, 2003 KR 10-2007-0053113 5/2007 KR 1020070053113 5/2007 (21) Appl. No.: 13/581,797 KR 1020070053113 A * 5, 2007 (22) PCT Filed: Apr. 15, 2011 WO WO O2/068367 9, 2002 OTHER PUBLICATIONS (86). PCT No.: IPRP for related PCT/KR2011/002692 issued on Oct. 23, 2012 and S371 (c)(1), its English translation. (2), (4) Date: Aug. 29, 2012 ISR for related PCT/KR2011/002692 mailed on Jan. 2, 2012 and its English translation. (87) PCT Pub. No.: WO2011/132888 Fumie Sato, et al. “Generation of a Silylethylene-Titanium Alkoxide Complex. -
Curriculum Vitae
1 CURRICULUM VITAE Robert Bau Born: February 10, 1944, Shanghai, China (naturalized U.S. citizen, 1974) Education: B.Sc., University of Hong Kong, June, 1964 Ph.D., University of California at Los Angeles, March, 1968 ` Postdoctoral Research Fellow, Harvard University, 1968-69 Positions Held Since Ph.D. Degree: 1977-present Professor of Chemistry, University of Southern California 1974-77 Associate Professor of Chemistry, University of Southern California 1969-74 Assistant Professor of Chemistry, University of Southern California Awards and Honors: Fellow of the Alfred P. Sloan Foundation, 1974-76 NIH Research Career Development Awardee, 1975-80 Recipient of USC Associates Award for Excellence in Teaching, 1974 Recipient of USC Associates Award for Excellence in Research, 1979 Fellow of the American Association for the Advancement of Science, 1982 Recipient of the Alexander van Humboldt Foundation, U.S. Senior Scientist Award, 1985 Visiting Professor of Chemistry, University of Grenoble, France, March-June, 1989 President, American Crystallographic Association, 2006 Research Interests: X-ray and Neutron Diffraction Studies of Covalent Metal Hydride Compounds Neutron Diffraction Studies on Molecules Having Chiral Methylene Groups (Molecules of the type CHDRR') Neutron Diffraction Studies of Small Proteins 2 PUBLICATION LIST Professor Robert Bau Department of Chemistry University of Southern California Los Angeles, California 90089-0744 1. "The Crystal Structure of HRe2Mn(CO)14. A Neutral, 'Electron Deficient', Polynuclear Carbonyl Hydride", H.D. Kaesz, R. Bau, and M.R. Churchill, J. Am. Chem. Soc., 89, 2775 (1967). 2. "Spectroscopic Studies of Isotopically Substituted Metal Carbonyls. I. Vibrational Analysis of Metal Pentacarbonyl Halides", H.D. Kaesz, R. Bau, D. Hendrickson and J.M. -
Synthetic Advances in the C‐H Activation of Rigid Scaffold Molecules
Synthesis Review Synthetic Advances in the C‐H Activation of Rigid Scaffold Molecules Nitika Grovera Mathias O. Senge*a a School of Chemistry, Trinity College Dublin, The University of Dublin, Trinity Biomedical Sciences Institute, 152–160 Pearse Street, Dublin 2, Ireland [email protected] Dedicated to Prof. Dr. Henning Hopf Received: only recall the epic endeavors involved in Eaton’s cubane Accepted: Published online: synthesis,3 Parquette’s preparation of dodecahedrane, DOI: Prinzbach’s pagodane route thereto, or Maier’s synthesis of Abstract The remarkable structural and electronic properties of rigid non‐ tetra-tert-butyltetrahedrane.4 conjugated hydrocarbons afford attractive opportunities to design molecular building blocks for both medicinal and material applications. The bridgehead positions provide the possibility to append diverse functional groups at specific angles and in specific orientations. The current review summarizes the synthetic development in CH functionalization of the three rigid scaffolds namely: (a) cubane, (b) bicyclo[1.1.1]pentane (BCP), (c) adamantane. 1 Introduction 2 Cubane 2.1 Cubane Synthesis 2.2 Cubane Functionalization 3 BCP 3.1 BCP Synthesis 3.2 BCP Functionalization 4 Adamantane 4.1 Adamantane Synthesis 4.2 Adamantane Functionalization 5 Conclusion and Outlook Key words Cubane, bicyclo[1.1.1]pentane, adamantane, rigid scaffolds, CH‐ functionalization. Figure 1 The structures of cubane, BCP and adamantane and the five platonic hydrocarbon systems. The fascinating architecture of these systems significantly 1 Introduction differs from scaffolds realized in natural compounds. Hence, they attracted considerable attention from synthetic and The practice of synthetic organic chemistry of non-natural physical organic chemists to investigate their properties and to compounds with rigid organic skeletons provides a deep establish possible uses.3,5 Significantly, over the past twenty understanding of bonding and reactivity. -
Cyclopentane Synthesis
Cyclopentane Synthesis Dan O’Malley Baran Group Meeting Cyclopentane Synthesis Group Meeting O'Malley 2/9/2005 This presentation is broken down into the following catagories. Some reactions either fit more than one Students of organic chemistry are taught a number of reactions for the synthesis of category or do not fit easily into any of them. Efforts have been made to place all such reactions in the cyclohexanes at a very early stage of their careers. Techniques for the creation of cyclopentanes, most appropriate category. however, are generally taught at a much later stage and are rarely given the same detailed treatment. This may be the result of the fact that there are no equivalents of reactions such as the Diels-Alder and I. General Information Robinson Annulation in terms of generality, extent of use, and historical importance. This may, in turn, II. Ionic Reactions be caused by the fact that the cyclopentane is an inherintly "umpoled" functionality, as illustrated below. III. Metal Mediated Reactions IV. Radical Reactions FG V. Pericyclic and Pseudo-pericyclic Reactions VI. Ring Expansion and Contraction Reactions I. General Information This situation is further exacerbated by the general lack of cheaply available cyclopentane compounds Baldwin's rules in the chiral pool; wheras a number of cyclohexane terpenes are readily available for elaboration, there Baldwin has divided ring closure reactions into those that are "favored" and those that are "disfavored". are no analogous cylcopentane natural products. Cyclopentanes are however, present in many Those that are disfavored are not always impossible, but are frequently much more difficult to effect. -
Cyclophane. Do MM Calculations of Each of These
10 52. Shown to the right are [2.2.2](1,3,5)-cyclophane and [2.2.2.2](1,2,3,5)-cyclophane. Do MM calculations of each of these as well as on all of the other two-carbon bridged structures: (1,2,3)-, (1,2,4)-, (1,2,3,4)-, (1,2,4,5)-, (1,2,3,4,5)-, and (1,2,3,4,5,6)-cyclophane; the latter is known as "superphane." Compare the computed angles and distances with those measured by X-ray crystallography (see the cited article). [Sekine, Y.; Boekelheide, V. J. Am. Chem. Soc. 1991, 103, 1777 and references cited therein; also Gleiter, R.; Kratz, D. Acc. Chem. Res. 1993, 26, 311.] 53. Shown to the right is [3.3](1,3)-cyclophane. There are at least five reasonable conformations for this compound (see the cited article). Use molecular mechanics to calculate the energy and geometry of each of these five conformations; assess which factors are responsible for the energy differences among the conformations. [Biali, S. E. J. Chem. Educ. 1990, 67, 1039.] 54. Use molecular mechanics to calculate the energies and geometries of a series of tetrasubstituted alkenes where R is H, Me, Et, iPr, or tBu. Compare your answers with those in Chart I and Table III of the first-cited reference. (Don't bother trying to reproduce the rotational barriers of Chart II because these are in doubt, as indicated by the second-cited reference.) [Clennan, E. L.; Chen, X.; Koola, J. J. J. Am. Chem. Soc. 1990, 112, 5193; Orfanopoulos, M.; Stratakis, M.; Elemes, Y.; Jensen, F. -
Bonding and Structure of Disilenes and Related Unsaturated Group-14 Element Compounds
No. 5] Proc. Jpn. Acad., Ser. B 88 (2012) 167 Review Bonding and structure of disilenes and related unsaturated group-14 element compounds † By Mitsuo KIRA*1, (Communicated by Hitosi NOZAKI, M.J.A.) Abstract: Structure and properties of silicon-silicon doubly bonded compounds (disilenes) are shown to be remarkably different from those of alkenes. X-Ray structural analysis of a series of acyclic tetrakis(trialkylsilyl)disilenes has shown that the geometry of these disilenes is quite flexible, and planar, twist or trans-bent depending on the bulkiness and shape of the trialkylsilyl substituents. Thermal and photochemical interconversion between a cyclotetrasilene and the corresponding bicyclo[1.1.0]tetrasilane occurs via either 1,2-silyl migration or a concerted electrocyclic reaction depending on the ring substituents without intermediacy of the corresponding tetrasila-1,3-diene. Theoretical and spectroscopic studies of a stable spiropentasiladiene have revealed a unique feature of the spiroconjugation in this system. Starting with a stable dialkylsilylene, a number of elaborated disilenes including trisilaallene and its germanium congeners are synthesized. Unlike carbon allenes, the trisilaallene has remarkably bent and fluxional geometry, suggesting the importance of the :-<* orbital mixing. 14-Electron three-coordinate disilene- palladium complexes are found to have much stronger :-complex character than related 16-electron tetracoordinate complexes. Keywords: silicon, germanium, double bond, synthesis, structure, theoretical calculations -
Synthesis and Characterization of 1,4-Dichlorospiropentadiene
TETRAHEDRON LETI'ERS Tetrahedron Letters 40 (1999) 6157-6158 Pergamon Synthesis and Characterization of 1,4-Dichlorospiropentadiene Rajesh K. Saini, Viadislav A. Litosh, Andrew D. Danlels, and W. E. Biilups* Department of Chemistry, Rice University, Houston, Texas 77005 Received 22 March 1999; revised 8 June 1999; accepted 14 June 1999 Abstract: 1,4-Dichlorospiropentadienewas prepared by vacuum gas-sofid elimination of compound 3 over solid (n-Bu)4N+ F" and characterizedby IH and 13C NMR spectroscopyat -103 °C. © 1999 Elsevier Science Ltd. All fights reserved. The possibility that double bonds arranged perpendicularly in space might interact by conjugation has generated considerable interest in molecules with geometry suitable for this interaction. 1,2 Spiropentadiene 1 is of interest in this regard and although the parent hydrocarbon has been reported recently, 3 simple derivatives of this ring system have not been reported. Recent theoretical calculations lead to a standard heat of formation of 157.4 kcal/mole for 1. 4 This is more than twice the experimental heat of formation of 66.2 kcal/mole for cyclopropene. We present here the synthesis and some of the properties of 1,4-dichlorospiropentadiene 2. C1 z C1 1 :~ The starting material, compound 3, 5 was prepared in 75% yield by refluxing a solution of 1,3- trimethylsilylallene 3 4 and PhHgCBrC126 in benzene for 48 hours. Elimination of trimethylsilylchioride from 3 to yield 2 using solid n-Bu4N + F- adsorbed on glass helices as described previously for I could be effected Me3Si \ /H Me3Si~¢~CIc1 ~CI I~ PhHgCBrC12 n-Bu4 N÷ F- I~ benzene I~C? 20mtorr " MeaSi/C~ H Me3Si 25 °C CI 4 3 2 in vacuo at 25 °C. -
A Stable Bicyclic Compound with Two Si¢Si Double Bonds
R EPORTS product analyses of a few chemical-trapping reactions (12, 13). The present results demon- A Stable Bicyclic Compound strate that the chemistry of Si¢Si double bonds ¢ is not as limited as had been assumed, and it with Two Si Si Double Bonds may even have comparable importance to or- ganic alkene chemistry. Takeaki Iwamoto, Makoto Tamura, Chizuko Kabuto, Mitsuo Kira* Compound 1. In contrast to carbon, silicon does not readily form double bonds, and com- pounds containing silicon-silicon double bonds can usually be stabilized only by protection with bulky substituents. We have isolated a silicon analog of spi- ropentadiene 1, a carbon double-ring compound that has not been isolated to date. In the crystal structure of tetrakis[tri(t-butyldimethylsilyl)silyl]spiro- pentasiladiene 2, a substantial deviation from the perpendicular arrangement of the two rings is observed, and the silicon-silicon double bonds are shown to be distorted. Spectroscopic data indicate pronounced interaction between two We have found that tetrakis[tri(tert-bu- remote silicon-silicon double bonds in the molecule. Silicon-silicon bonds may tyldimethylsilyl)silyl]spiropentasiladiene (2) be more accessible to synthesis than previously assumed. forms as a by-product during the preparation of cyclotrisilene 3 (Eq. 1) (7). The reaction of 4 In contrast to alkenes, Si¢Si doubly bonded isolated to date (11). Parent spiropentadiene 1 with potassium graphite at Ϫ78°C and subse- compounds (disilenes) are usually unstable and and 1,1Ј-dichlorinated spiropentadiene have quent work-up resulted in a brownish red solid, can only be isolated when the double bonds are been generated in solution but decompose with- which contained spiropentasiladiene 2 and cy- protected effectively by bulky substituents. -
4.3.6 Strain Energies and Heats of Formation
Results and Discussion • 183 ∆ –1 dramatically reduces the barrier to inversion ( Eplan drops from 58.6 to 7.4 kJ mol ). This might partly reflect the dramatic reduction in the energy difference between ‘pla- ∆ nar’ and tetrahedral-like structures for neopentane and spiropentane ( EPT = 880 and 440 kJ mol–1, respectively) (see Section 4.3.2). The introduction of a pair of methylene bridges between the caps then reduces this barrier to zero, giving a broadened potential energy well with an equilibrium structure with D2h symmetry. 4.3.6 Strain Energies and Heats of Formation Determining the total strain energies (SEs) of our novel hydrocarbons allows for a comparison with other strained hydrocarbons.43 We have chosen to use a method of cal- culating strain energies which has been used to great effect by Schulman and Disch.32 This method determines the strain energy as the negative of the calculated enthalpy change of a homodesmic reaction in which the number of quaternary (C), tertiary (CH) and secondary (CH2) carbons present in the target hydrocarbon are balanced with prod- uct neopentane, isobutane and propane molecules. The number of primary (CH3) car- bons on each side of the reaction is then balanced using ethane. This preserves the number and type of C–C bonds on each side of the reaction and is found to give good cancellation of errors when the MP2 method is used to calculate energies (see also Section 3.2 on page 97). If these product molecules are defined as being strain free (which is usual), the enthalpy change of this homodesmic reaction gives the total strain of the target hydrocarbon. -
Prakash Vita-September 2018
VITA G. K. Surya Prakash (October 2018) PERSONAL DATA Born: October 7, 1953, Bangalore, India Citizenship: USA (Naturalized) Married: 1981, Rama Devi Children: Archana, daughter (b. 1985), Arjun, son (b. 1991). Address: Home: 3412 Casco Court, Hacienda Heights, CA 91745, U. S. A Office: Loker Hydrocarbon Research Institute, University of Southern California, 837 Bloom Walk, Los Angeles, CA 90089- 1661, U.S.A. Telephone: (H) 626-333-734; (O) 213-740-5984; Fax: 213-740-6679 Email: [email protected] Web Address: http://chem.usc.edu/faculty/Prakash.html EDUCATION B. Sc (Honors) Chemistry, Bangalore University, India, 1972 M.Sc., Chemistry, Indian Institute of Technology (IIT), Madras, India, 1974 Ph. D., Chemistry, University of Southern California (Under Nobel Laureate, Professor George A. Olah), 1978 (Ph.D. work was carried out at Case Western Reserve University, 1974-1977) Postdoctoral, 1978-1979, University of Southern California (Nobel Laureate, Professor George A. Olah) ACADEMIC EXPERIENCE and POSITIONS Chairman, Department of Chemsitry, University of Southern California, 2017-present. Director, Loker Hydrocarbon Research Institute, University of Southern California, Sept. 2010- present. Scientific Director, Loker Hydrocarbon Research Institute, University of Southern California, Feb. 2000- August 2010. George A. & Judith A. Olah Nobel Laureate Chair in Hydrocarbon Chemistry, University of Southern California, Jan. 1997 – present. Professor of Chemistry, University of Southern California, Sept.1994 – present. Associate Professor of Chemistry, University of Southern California, Sept. 1990- Aug.1994, Tenured in 1993. Research Associate Professor of Chemistry, University of Southern California, Sept. 1984-Aug.1990. Research Assistant Professor of Chemistry, University of Southern California, Sept. 1981 – Aug. 1984. Junior Fellow, Loker Hydrocarbon Research Institute, University of Southern California, March 1979- Aug.1981.