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Duecker FL, Heinze RC, Heretsch P. Synthesis of Swinhoeisterol A, Dankasterone A and B, and Periconiastone A by Radical Framework Reconstruction. J Am Chem Soc 2019; 142:104-108. [DOI: 10.1021/jacs.9b12899] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Fenja L. Duecker
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - Robert C. Heinze
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - Philipp Heretsch
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
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2
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Qin T, Cornella J, Li C, Malins LR, Edwards JT, Kawamura S, Maxwell BD, Eastgate MD, Baran PS. A general alkyl-alkyl cross-coupling enabled by redox-active esters and alkylzinc reagents. Science 2016; 352:801-5. [PMID: 27103669 PMCID: PMC4867118 DOI: 10.1126/science.aaf6123] [Citation(s) in RCA: 528] [Impact Index Per Article: 66.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 04/11/2016] [Indexed: 12/29/2022]
Abstract
Alkyl carboxylic acids are ubiquitous in all facets of chemical science, from natural products to polymers, and represent an ideal starting material with which to forge new connections. This study demonstrates how the same activating principles used for decades to make simple C-N (amide) bonds from carboxylic acids with loss of water can be used to make C-C bonds through coupling with dialkylzinc reagents and loss of carbon dioxide. This disconnection strategy benefits from the use of a simple, inexpensive nickel catalyst and exhibits a remarkably broad scope across a range of substrates (>70 examples).
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Affiliation(s)
- Tian Qin
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Josep Cornella
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Chao Li
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Lara R Malins
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jacob T Edwards
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Shuhei Kawamura
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Brad D Maxwell
- Discovery Chemistry Platforms-Radiochemistry, Bristol-Myers Squibb, Post Office Box 4000, Princeton, NJ, USA
| | - Martin D Eastgate
- Chemical Development, Bristol-Myers Squibb, One Squibb Drive, New Brunswick, NJ 08903, USA
| | - Phil S Baran
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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3
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Walton JC. The importance of chain conformational mobility during 5-exo-cyclizations of C-, N- and O-centred radicals. Org Biomol Chem 2015; 12:7983-92. [PMID: 25179567 DOI: 10.1039/c4ob01419g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction coordinates of an archetypical set of 5-exo cyclizations of C-, N- and O-centred radicals were investigated by computational methods. G4 theory, and DFT with the um062x functional, were able to rationalise counterintuitive factors such as the 'normal' order of rate constants being: N-centred < C-centred < O-centred radicals. The access angle between the radical centre and the double bond was identified as a key factor. Examination of its evolution during ring closure implied that rigidity at the N-ends of the chains, and the consequent extra energy needed to attain chair-like transition states, might be the reason for slow aminyl cyclizations. A novel linear correlation between cyclization activation energies and the access angles was discovered. The preference for cis-1,2-disubstituted product formation was also accounted for in terms of interaction between the hyperconjugatively delocalized SOMO and the alkene π* orbital.
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Affiliation(s)
- John C Walton
- University of St. Andrews, EaStCHEM School of Chemistry, St. Andrews, Fife, KY16 9ST, UK.
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Portela-Cubillo F, Alonso-Ruiz R, Sampedro D, Walton JC. 5-Exo-Cyclizations of Pentenyliminyl Radicals: Inversion of the gem-Dimethyl Effect. J Phys Chem A 2009; 113:10005-12. [DOI: 10.1021/jp9047902] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fernando Portela-Cubillo
- School of Chemistry, University of St. Andrews, EaStChem, St. Andrews, Fife, KY16 9ST, U.K., and Departamento de Química, Universidad de La Rioja, Grupo de Síntesis Química de La Rioja, Unidad Asociada al CSIC, Madre de Dios, 51, 26006, Logroño, Spain
| | - Rafael Alonso-Ruiz
- School of Chemistry, University of St. Andrews, EaStChem, St. Andrews, Fife, KY16 9ST, U.K., and Departamento de Química, Universidad de La Rioja, Grupo de Síntesis Química de La Rioja, Unidad Asociada al CSIC, Madre de Dios, 51, 26006, Logroño, Spain
| | - Diego Sampedro
- School of Chemistry, University of St. Andrews, EaStChem, St. Andrews, Fife, KY16 9ST, U.K., and Departamento de Química, Universidad de La Rioja, Grupo de Síntesis Química de La Rioja, Unidad Asociada al CSIC, Madre de Dios, 51, 26006, Logroño, Spain
| | - John C. Walton
- School of Chemistry, University of St. Andrews, EaStChem, St. Andrews, Fife, KY16 9ST, U.K., and Departamento de Química, Universidad de La Rioja, Grupo de Síntesis Química de La Rioja, Unidad Asociada al CSIC, Madre de Dios, 51, 26006, Logroño, Spain
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5
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Majumdar KC, Kundu N. Regioselective synthesis of bioactive spiro heterocyclic compounds containing both indoline and quinolone moieties by aryl radical cyclization. J Heterocycl Chem 2009. [DOI: 10.1002/jhet.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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6
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DeZutter CB, Horner JH, Newcomb M. Rate Constants for 1,5- and 1,6-Hydrogen Atom Transfer Reactions of Mono-, Di-, and Tri-aryl-substituted Donors, Models for Hydrogen Atom Transfers in Polyunsaturated Fatty Acid Radicals. J Phys Chem A 2008; 112:1891-6. [PMID: 18269270 DOI: 10.1021/jp710750f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher B. DeZutter
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607
| | - John H. Horner
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607
| | - Martin Newcomb
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607
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7
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Majumdar KC, Kundu N. Carbon–Carbon Bond Formation by Radical Cyclization: Regioselective Synthesis ofSpiroHeterocyclic Compounds bynBu3SnH‐Mediated Reaction. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397910600602602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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8
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Hodgson DM, Hachisu S, Andrews MD. Stereocontrolled syntheses of kainoid amino acids from 7-azabicyclo[2.2.1]heptadienes using tandem radical addition-homoallylic radical rearrangement. J Org Chem 2006; 70:8866-76. [PMID: 16238320 DOI: 10.1021/jo0513865] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction; see text] N-Boc syn-7-(2-hydroxyethyl)-4-(alkyl or aryl)sulfonyl-2-azabicyclo[2.2.1]hept-5-enes serve as precursors in syntheses of the neuroexcitants 3-(carboxymethyl)pyrrolidine-2,4-dicarboxylic acid 43, alpha-kainic acid 12, alpha-isokainic acid 14, and alpha-dihydroallokainic acid 77. The key step in these syntheses is the intermolecular radical addition of 2-iodoethanol to a N-Boc 2-(alkyl or aryl)sulfonyl-7-azabicyclo[2.2.1]heptadiene 7 to induce nitrogen-directed homoallylic radical rearrangement. Oxidative cleavage of the resulting 2-azabicyclo[2.2.1]hept-5-enes provide straightforward access to polysubstituted pyrrolidines and, in particular, an efficient entry to the kainoid amino acids.
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Affiliation(s)
- David M Hodgson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, UK.
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9
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Zimmermann G, Nüchter M, Remmler M, Findeisen M, Hopf H, Ernst L, Mlynek C. Das Thermogramm einer C
6
H
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‐Chemie im Temperaturbereich von 450 bis 730°C. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19941270926] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Gerhard Zimmermann
- Abteilung Hochtemperaturreaktionen am Institut für Technische Chemie der Universität Leipzig, Permoserstraße 15, D‐04303 Leipzig, Germany
| | - Matthias Nüchter
- Abteilung Hochtemperaturreaktionen am Institut für Technische Chemie der Universität Leipzig, Permoserstraße 15, D‐04303 Leipzig, Germany
| | - Matthias Remmler
- UFZ — Umweltforschungszentrum Leipzig‐Halle GmbH, Sektion Sanierungsforschung, Permoserstraße 15, D‐04303 Leipzig, Germany
| | - Matthias Findeisen
- Institut für Analytische Chemie der Universität Leipzig, Linnéstr. 3, D‐04103 Leipzig, Germany
| | - Henning Hopf
- Institut für Organische Chemie der Technischen Universität Braunschweig, Postfach 3329, D‐38023 Braunschweig, Germany
| | - Ludger Ernst
- Institut für Organische Chemie der Technischen Universität Braunschweig, Postfach 3329, D‐38023 Braunschweig, Germany
| | - Cornelia Mlynek
- Institut für Organische Chemie der Technischen Universität Braunschweig, Postfach 3329, D‐38023 Braunschweig, Germany
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10
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11
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12
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Hodgson DM, Hachisu S, Andrews MD. Synthesis of alpha-kainic acid from a 7-azabicyclo[2.2.1]heptadiene by tandem radical addition-homoallylic radical rearrangement. Org Lett 2005; 7:815-7. [PMID: 15727448 DOI: 10.1021/ol047557u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reductive radical addition of 2-iodoethanol to N-Boc 2-tosyl-7-azabicyclo[2.2.1]heptadiene gives N-Boc syn-7-(2-hydroxyethyl)-4-tosyl-2-azabicyclo[2.2.1]hept-5-ene, which is converted into the neuroexcitants 3-(carboxymethyl)pyrrolidine-2,4-dicarboxylic acid and alpha-kainic acid. [structure: see text]
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Affiliation(s)
- David M Hodgson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford OX1 3TA, UK.
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13
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Aeberhard U, Keese R, Stamm E, Vögeli UC, Lau W, Kochi JK. Structure and Chemistry of Malonylmethyl- and Succinyl-Radicals. The search for homolytic 1,2-rearrangements. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19830660843] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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14
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Rüegge D, Fischer H. Rate constants for the decarboxylation of thet-butoxicarbonyl radical and concurring radical terminations directly obtained by kinetic ESR. INT J CHEM KINET 2004. [DOI: 10.1002/kin.550180202] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Foray GS, Peñéñory AB, Rossi RA. Nucleophilic substitution at nitrogen-centered radicals: Reactions of diphenylphosphide ions withN,N-dibutyl-p-toluenesulfonamide by theSRN1 mechanism. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.610080507] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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16
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C. Majumdar K, P. Mukhopadhyay P, K. Basu P. Formation of Five- and Six-membered Heterocyclic Rings by Radical Cyclization. HETEROCYCLES 2004. [DOI: 10.3987/rev-04-577] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Hodgson DM, Bebbington MWP, Willis P. 2-azabenzonorbornanes from 7-azabenzonorbornanols by a nitrogen-directed neophyl-type radical rearrangement. Org Lett 2002; 4:4353-6. [PMID: 12443096 DOI: 10.1021/ol027039o] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] Barton deoxygenation of 7-azabenzonorbornanols leads to a synthetically useful neophyl-like rearrangement to give 2-azabenzonorbornane derivatives in 64-90% yields.
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Affiliation(s)
- David M Hodgson
- Dyson Perrins Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QY, UK.
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18
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Chatgilialoglu C, Ferreri C, Guerra M, Timokhin V, Froudakis G, Gimisis T. 5-Endo-trig radical cyclizations: disfavored or favored processes? J Am Chem Soc 2002; 124:10765-72. [PMID: 12207532 DOI: 10.1021/ja0261731] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Relative kinetic data were determined for the 5-endo-trig cyclization of radical 12 compared to hydrogen abstraction from (TMS)(3)SiH in the temperature range of 344-430 K, which allows for the estimation of a rate constant of 2 x 10(4) s(-)(1) at 298 K with an activation energy of ca. 9 kcal/mol for the cyclization process. The 5-endo-trig cyclization of a variety of radicals that afford five-membered nitrogen-containing heterocycles was addressed computationally at the UB3LYP/6-31G level. The 5-endo vs 4-exo mode of cyclication and the effect of delocalization of the unpaired electron in the transition state were investigated. Because the ring formed during cyclization contains five sp(2) centers, electrocyclization via a pentadienyl-like resonance form was also considered. For comparison, similar calculations were performed for 4-penten-1-yl and related radicals. The factors that affect the activation energies of homolytic 5-endo-trig cyclization were determined. In the absence of steric or conformational effects, the endo cyclization to form the five-membered ring was strongly favored over exo cyclization to form the four-membered ring not only on thermodynamic grounds but also kinetically. When a substituent on the double bond was able to delocalize the unpaired electron in the transition state of the 4-exo path, the two modes of cyclization became kinetically comparable. These results have an important bearing on the generalization of the Baldwin-Beckwith rules, which classified the 5-endo-trig radical cyclization as a "disfavored" process.
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19
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de Meijere A, von Seebach M, Zöllner S, Kozhushkov SI, Belov VN, Boese R, Haumann T, Benet-Buchholz J, Yufit DS, Howard JA. Spirocyclopropanated bicyclopropylidenes: straightforward preparation, physical properites, and chemical transformations. Chemistry 2001; 7:4021-34. [PMID: 11596945 DOI: 10.1002/1521-3765(20010917)7:18<4021::aid-chem4021>3.0.co;2-e] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Perspirocyclopropanated bicyclopropylidene (6) was prepared in three steps from 7-cyclopropylidenedispiro[2.0.2.1]heptane (4) (24% overall) or, more efficiently, through dehalogenative coupling of 7,7-dibromo[3]triangulane (15) (82%). This type of reductive dimerization turned out to be successful for the synthesis of (E)- and (Z)-bis(spiropentylidene) 14 (67%) and even of the "third-generation" spirocyclopropanated bicyclopropylidene 17 (17% overall from 15). Whereas the parent bicyclopropylidene 1 dimerized at 180 degrees C to yield [4]rotane, dimerization of 6 at 130 degrees C under 10 kbar pressure occured only with opening of one three-membered ring to yield the polyspirocyclopropanated (cyclopropylidene)cyclopentane derivative 19 (34% yield), and at the elevated temperature the polyspirocyclopropanated 2-cyclopropylidene[3.2.2]propellane derivative 20 (25 % yield). Perspirocyclopropanated bicyclopropylidene 6 and the "third-generation" bicyclopropylidene 17 gave addition of bromine, hydrogen bromide, and various dihalocarbenes without rearrangement. The functionally substituted branched [7]triangulane 28 and branched dichloro-C2v-[15]triangulane 32 were used to prepare the perspirocyclopropanated [3]rotane (D3h-[10]triangulane) 49 (six steps from 6, 1.4% overall yield) and the C2v-[15]triangulane 51 (two steps from 17, 41% overall). Upon catalytic hydrogenation, the perspirocyclopropanated bicyclopropylidene 6 yielded 7,7'-bis(dispiro[2.0.2.]-heptyl) (52) and, under more forcing conditions, 1,1'-bis(2,2,3,3-tetramethylcyclopropyl) (53). The bromofluorocarbene adduct 33 of 17 reacted with butyllithium to give the unexpected polyspirocyclopropanated 1,4-di-n-butyl-2-cyclopropylidenebicyclo[2.2.0]hexane derivative 37 as the main product (55% yield) along with the expected "third-generation" perspirocyclopropanated dicyclopropylidenemethane 38 (21% yield). Mechanistic aspects of this and the other unusual reactions are discussed. The structures of all new unusual hydrocarbons were proven by X-ray crystal structure analyses, and the most interesting structural and crystal packing features are presented.
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Affiliation(s)
- A de Meijere
- Institut für Organische Chemie, Georg-August-Universität Göttingen, Germany.
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20
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McCarroll AJ, Walton JC. Programmierung organischer Moleküle: Design und Management organischer Synthesen über radikalische Kaskaden. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010618)113:12<2282::aid-ange2282>3.0.co;2-f] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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21
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Ihee H, Kua J, Goddard WA, Zewail AH. CF2XCF2X and CF2XCF2• Radicals (X = Cl, Br, I): Ab Initio and DFT Studies and Comparison with Experiments. J Phys Chem A 2001. [DOI: 10.1021/jp004035x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hyotcherl Ihee
- Arthur Amos
Noyes Laboratory of Chemical Physics (127-72), Materials and Process
Simulation Center,
Beckman Institute (139−74), and Division of Chemistry and Chemical
Engineering,
California Institute of Technology, Pasadena, California 91125
| | - Jeremy Kua
- Arthur Amos
Noyes Laboratory of Chemical Physics (127-72), Materials and Process
Simulation Center,
Beckman Institute (139−74), and Division of Chemistry and Chemical
Engineering,
California Institute of Technology, Pasadena, California 91125
| | - William A. Goddard
- Arthur Amos
Noyes Laboratory of Chemical Physics (127-72), Materials and Process
Simulation Center,
Beckman Institute (139−74), and Division of Chemistry and Chemical
Engineering,
California Institute of Technology, Pasadena, California 91125
| | - Ahmed H. Zewail
- Arthur Amos
Noyes Laboratory of Chemical Physics (127-72), Materials and Process
Simulation Center,
Beckman Institute (139−74), and Division of Chemistry and Chemical
Engineering,
California Institute of Technology, Pasadena, California 91125
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22
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Senboku H, Hasegawa H, Orito K, Tokuda M. Exclusive 1,4-aryl migration in a stereoselective cyclization of N-benzylalk-4-enylaminyl radicals. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)00933-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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23
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Characterization, via ESR spectroscopy, of radical intermediates in the photooxidation of arylcarbinols by ceric ammonium nitrate. J Org Chem 2000; 65:2748-54. [PMID: 10808450 DOI: 10.1021/jo991856t] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photooxidation by ceric ammonium nitrate (CAN) of several aryl and naphthylcarbinols has been studied by means of ESR spectroscopy. For all the investigated arylcarbinols, but not for the naphthyl derivatives, it has been possible to detect radical intermediates deriving from the parent alkoxyl radicals. In particular, in the photooxidation of 1,1-diphenylethanol, a bridged-radical intermediate has been detected. The assignment has been validated through experiments with two different labeled compounds: the 1,1-[2', 3', 4', 5', 6', 2", 3", 4", 5", 6"-2H10]diphenylethanol and the 1,1-diphenyl[2, 2, 2-2H3]ethanol. A similar bridged radical has been found to be formed in the photooxidation of triphenylmethanol, while, for the 1,1-diphenylpropanol, the only detectable species has been the ethyl radical deriving from a competitive beta-scission process. Finally, for the 2-phenylpropan-2-ol (cumyl alcohol), two radical species have been identified: the methyl, deriving from the beta-scission process, and the cyanomethylene, deriving from H-abstraction of the cumyloxyl radical from the solvent. A kinetic study on the competition of the two processes has also been conducted and the parameters of the Arrhenius equation for the latter process have been estimated.
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24
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de Meijere A, Kozhushkov SI. The chemistry of highly strained oligospirocyclopropane systems. Chem Rev 2000; 100:93-142. [PMID: 11749235 DOI: 10.1021/cr960153y] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A de Meijere
- Institut für Organische Chemie der Georg-August-Universität Göttingen, Tammannstrasse 2, D-37077 Göttingen, Germany
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25
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Chang SY, Shao YF, Chu SF, Fan GT, Tsai YM. A Novel 1,3-Stannyl Shift Promoted Intramolecular Cyclizations of α-Stannyl Radicals with a Formyl Group. Org Lett 1999. [DOI: 10.1021/ol990199o] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sheng-Yueh Chang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Yar-Fang Shao
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Shu-Fang Chu
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Gang-Ting Fan
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Yeun-Min Tsai
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
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26
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Navarrini W, Tortelli V, Russo A, Corti S. Organic hypofluorites and their new role in industrial fluorine chemistry. J Fluor Chem 1999. [DOI: 10.1016/s0022-1139(98)00296-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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27
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Leardini R, Lucarini M, Pedulli GF, Valgimigli L. Synthesis and Calibration of Two Radical Timing Devices: 2-Methyl-2-(1-naphthyl)- and 2-Methyl-2-(2-naphthyl)- 1-bromopropane. J Org Chem 1999; 64:3726-3730. [PMID: 11674505 DOI: 10.1021/jo9813179] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rino Leardini
- Dipartimento di Chimica Organica "A. Mangini", Università di Bologna, Via S. Donato 15, 40127 Bologna, Italy
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28
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Shtarev AB, Dolbier, WR, Smart BE. Rates of 1,5-Hydrogen Abstraction in 1,1,2,2-Tetrafluoro-n-pentyl and 1,1,2,2,3,3-Hexafluoro-n-pentyl Radicals. J Am Chem Soc 1999. [DOI: 10.1021/ja9830344] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alexander B. Shtarev
- Contribution from the Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and DuPont Central Research & Development, Experimental Station, Wilmington, Delaware 19880-03278
| | - William R. Dolbier,
- Contribution from the Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and DuPont Central Research & Development, Experimental Station, Wilmington, Delaware 19880-03278
| | - Bruce E. Smart
- Contribution from the Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and DuPont Central Research & Development, Experimental Station, Wilmington, Delaware 19880-03278
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29
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Jiaang WT, Lin HC, Tang KH, Chang LB, Tsai YM. The Study of the Kinetics of Intramolecular Radical Cyclizations of Acylsilanes via the Intramolecular Competition Method. J Org Chem 1999. [DOI: 10.1021/jo982079k] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Weir-Torn Jiaang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Hsien-Chang Lin
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Kuo-Hsiang Tang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Lih-Bin Chang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
| | - Yeun-Min Tsai
- Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
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30
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Molander GA, Wolfe CN. Intramolecular Ketone−Nitrile Reductive Coupling Reactions Promoted by Samarium(II) Iodide. J Org Chem 1998. [DOI: 10.1021/jo981537m] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gary A. Molander
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado 80309-0215
| | - Chad N. Wolfe
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado 80309-0215
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31
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Kozhushkov SI, Brandl M, de Meijere A. Surprisingly Facile Addition of Thiols to the Double Bonds of Bicyclopropylidene and Other Methylenecyclopropanes. European J Org Chem 1998. [DOI: 10.1002/(sici)1099-0690(199808)1998:8<1535::aid-ejoc1535>3.0.co;2-p] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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32
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Beckwith ALJ, Page DM. Formation of Some Oxygen-Containing Heterocycles by Radical Cyclization: The Stereochemical Influence of Anomeric Effects. J Org Chem 1998. [DOI: 10.1021/jo980359u] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Athelstan L. J. Beckwith
- Research School of Chemistry, and Department of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - Dennis M. Page
- Research School of Chemistry, and Department of Chemistry, Australian National University, Canberra, ACT 0200, Australia
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33
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Tsai JY, Shevlin PB. Structure of the Products of the Cyclooligomerization of Sulfur Dioxide with Diethyl Diallylmalonate. J Org Chem 1998. [DOI: 10.1021/jo9718915] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jui-Yi Tsai
- Department of Chemistry, Auburn University, Auburn, Alabama 36849-5312
| | - Philip B. Shevlin
- Department of Chemistry, Auburn University, Auburn, Alabama 36849-5312
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34
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Starnes, WH, Zaikov VG, Chung HT, Wojciechowski BJ, Tran HV, Saylor K, Benedikt GM. Intramolecular Hydrogen Transfers in Vinyl Chloride Polymerization: Routes to Doubly Branched Structures and Internal Double Bonds. Macromolecules 1998. [DOI: 10.1021/ma9711250] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- W. H. Starnes,
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - V. G. Zaikov
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - H. T. Chung
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - B. J. Wojciechowski
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - H. V. Tran
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - K. Saylor
- Department of Applied Science and Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - G. M. Benedikt
- BFGoodrich Company, Research and Development Center, Brecksville, Ohio 44141
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35
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Affiliation(s)
- John C. Walton
- University of St. Andrews, School of Chemistry, St. Andrews, Fife KY16 9ST, U.K
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36
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Okano T, Ishihara H, Takakura N, Tsuge H, Eguchi S, Kimoto H. Cyclization of Hindered Fluorinated Dichloro(5- and 6-)alkenyl Radicals. Structural Effects of Olefins on the Selective Formation of 5-exo and 6-endo Cyclization Products. J Org Chem 1997; 62:7192-7200. [PMID: 11671827 DOI: 10.1021/jo970639u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reaction of 3-butenyl radicals generated by photolysis of variously substituted Barton esters (both open-chain 1a-d and cyclohexyl 1e-h) with CF(2)=CCl(2) gave a mixture of cyclized products (cyclopentanes 6 and 8 and cyclohexanes 7 and 9) as well as noncyclized products (4and 5) in various ratios depending on the substitution pattern at the olefinic moiety. The product ratios of [cyclization (6 + 7 + 8 + 9):noncyclization (5)] for 1 with more alkyl substituents on the CC double bond were greater than those for 1 with fewer substituents. The products ratio of [5-exo (6 + 8):6-endo (7 + 9)] was influenced by a steric effect. Photoreaction of Barton ester 2 with CF(2)=CCl(2) gave a mixture of cyclohexanes 16 and 17 as well as noncyclized 14 and 15. Dehydrochlorination of decalins 7g and 7h followed by oxidation of sulfide and [2,3]sigmatropic rearrangement of the allyl sulfoxide gave octahydronaphthalenones 23 and 27, respectively.
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Affiliation(s)
- Takashi Okano
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-01, Japan, and National Industrial Research Institute of Nagoya, Hirate-cho, Kita-ku, Nagoya 462, Japan
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37
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Beaulieu F, Arora J, Veith U, Taylor NJ, Chapell BJ, Snieckus V. 1,3-Asymmetric Induction via 1,5-Hydrogen Atom Translocation Reactions. Highly Enantioselective Synthesis of β-Substituted β-Amino Acids. J Am Chem Soc 1996. [DOI: 10.1021/ja961484v] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Beaulieu
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
| | - J. Arora
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
| | - U. Veith
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
| | - N. J. Taylor
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
| | - B. J. Chapell
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
| | - V. Snieckus
- The Guelph-Waterloo Centre for Graduate Work in Chemistry, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
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38
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Malacria M. Selective Preparation of Complex Polycyclic Molecules from Acyclic Precursors via Radical Mediated- or Transition Metal-Catalyzed Cascade Reactions. Chem Rev 1996; 96:289-306. [PMID: 11848754 DOI: 10.1021/cr9500186] [Citation(s) in RCA: 351] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Max Malacria
- Laboratoire de Chimie Organique de Synthèse, Université Pierre et Marie Curie (Paris VI), URA CNRS 408, Tour 44-54, B.P 229, 4 Place Jussieu, 75252 Paris Cedex 05, France
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Curran DP, Xu J. o-Bromo-p-methoxyphenyl Ethers. Protecting/Radical Translocating (PRT) Groups That Generate Radicals from C−H Bonds β to Oxygen Atoms. J Am Chem Soc 1996. [DOI: 10.1021/ja954150z] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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40
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Elford PE, Roberts BP. EPR studies of the formation and transformation of isomeric radicals [C3H5O]˙. Rearrangement of the allyloxyl radical in non-aqueous solution involving a formal 1,2-hydrogen-atom shift promoted by alcohols. ACTA ACUST UNITED AC 1996. [DOI: 10.1039/p29960002247] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Alkoxy radicals in organic synthesis. A novel approach to a key intermediate in milbemycin chemistry. Tetrahedron Lett 1994. [DOI: 10.1016/s0040-4039(00)73322-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Berti C, Grierson L, Grimes JAM, Perkins MJ, Terem B. Reaktivität bei intramolekularen Radikalreaktionen – Vergleich zwischen Wasserstofftransfer und Alkenaddition. Angew Chem Int Ed Engl 1990. [DOI: 10.1002/ange.19901020615] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Johnson KM, Kirwan JN, Roberts BP. Homolytic reactions of ligated boranes. Part 14. ESR studies of ring opening of cycloalkylaminyl–borane radicals and reactions of aminyl–borane radicals with silicon-containing compounds. ACTA ACUST UNITED AC 1990. [DOI: 10.1039/p29900001125] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Polyspirane, 16. – Umlagerungskaskaden, 11. Synthese, Struktur, Konformation und Dynamik von Heptacyclo[19.3.0.01,5.05,9.09,13.013,17.017,21]tetracosan ([6.5]Coronan). ACTA ACUST UNITED AC 1988. [DOI: 10.1002/cber.19881211216] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Christl M, Henneberger H, Freund S. Halbkäfigverbindungen aus Polycyclen mit einem Bicylo[1.1.0]butan-System und dazu benachbarter Azobrücke durch Radikalreaktionen mit Thiophenol und Bromtrichlormethan. ACTA ACUST UNITED AC 1988. [DOI: 10.1002/cber.19881210921] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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Wehle D, Fitjer L. Heptacyclo[19.3.0.01,5.05,9.09,13.013,17.017,21]tetracosan ([6.5]Coronan). Angew Chem Int Ed Engl 1987. [DOI: 10.1002/ange.19870990210] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sakurai H. PHOTOCHEMISTRY OF DI(9-ANTHRYL)- AND BENZYL-SUBSTITUTED SILANES AND RELATED COMPOUNDS1. ACTA ACUST UNITED AC 1986. [DOI: 10.1080/03086648608072771] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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49
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Padwa A, Dent W, Nimmesgern H, Venkatramanan MK, Wong GSK. Utilization of phenylthio substituted amines for the synthesis of pyrrolidines. ACTA ACUST UNITED AC 1986. [DOI: 10.1002/cber.19861190305] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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O'Sullivan A, Bischofberger N, Frei B, Jeger O. Thermal Reactions of Epoxyenones and Epoxydienes in the Ionone Series. Helv Chim Acta 1985. [DOI: 10.1002/hlca.19850680503] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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