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Glotz G, Drusgala M, Hamm F, Fischer RC, Došlić N, Kelterer AM, Gescheidt G, Haas M. Wavelength-dependent rearrangements of an α-dione chromophore: a chemical pearl in a bis(hypersilyl) oyster. Chem Sci 2024; 15:4427-4433. [PMID: 38516088 PMCID: PMC10952070 DOI: 10.1039/d4sc00064a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 02/14/2024] [Indexed: 03/23/2024] Open
Abstract
The symmetric bissilyl-dione 3 reveals two well-separated n → π* absorption bands at λmax = 637 nm (ε = 140 mol-1 dm3 cm-1) and 317 nm (ε = 2460 mol-1 dm3 cm-1). Whereas excitation of 3 at λ = 360/365 nm affords an isolable siloxyketene 4 in excellent yields, irradiation at λ = 590/630 nm leads to the stereo-selective and quantitative formation of the siloxyrane 5. These remarkable wavelength-dependent rearrangements are based on the electronic and steric properties provided by the hypersilyl groups. While the siloxyketene 4 is formed via a hitherto unknown 1,3-hypersilyl migration via the population of a second excited singlet state (S2, λmax = 317 nm, a rare case of anti-Kasha reactivity), the siloxyrane 5 emerges from the first excited triplet state (T1via S1λmax = 637 nm). These distinct reaction pathways can be traced back to specific energy differences between the S2, S1 and T1, an electronic consequence of the bissilyl substited α-dione (the "pearl"). The hypersilyl groups act as protective ''oyster shell", which are responsible for the clean formation of 4 and 5 basically omitting side products. We describe novel synthetic pathways to achieve hypersilyl substitution (3) and report an in-depth investigation of the photorearrangements of 3 using UV/vis, in situ IR, NMR spectroscopy and theoretical calculations.
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Affiliation(s)
- Gabriel Glotz
- Institute of Physical and Theoretical Chemistry, Graz University of Technology Stremayrgasse 9/II 8010 Graz Austria
| | - Manfred Drusgala
- Institute of Inorganic Chemistry, Graz University of Technology Stremayrgasse 9/IV 8010 Graz Austria
| | - Florian Hamm
- Institute of Physical and Theoretical Chemistry, Graz University of Technology Stremayrgasse 9/II 8010 Graz Austria
| | - Roland C Fischer
- Institute of Inorganic Chemistry, Graz University of Technology Stremayrgasse 9/IV 8010 Graz Austria
| | - Nađa Došlić
- Department of Physical Chemistry, Ruđer Bošković Institute Bijenička 54 Zagreb Croatia
| | - Anne-Marie Kelterer
- Institute of Physical and Theoretical Chemistry, Graz University of Technology Stremayrgasse 9/II 8010 Graz Austria
| | - Georg Gescheidt
- Institute of Physical and Theoretical Chemistry, Graz University of Technology Stremayrgasse 9/II 8010 Graz Austria
| | - Michael Haas
- Institute of Inorganic Chemistry, Graz University of Technology Stremayrgasse 9/IV 8010 Graz Austria
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Lukáč I, Husár B, Danko M, Weiss RG. Benzil Photoperoxidations in Polymer Films and Crosslinking by the Resultant Benzoyl Peroxides in Polystyrene and Other Polymers. Molecules 2021; 26:molecules26175154. [PMID: 34500588 PMCID: PMC8434379 DOI: 10.3390/molecules26175154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/10/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022] Open
Abstract
Benzil (BZ) can be converted almost quantitatively to benzoyl peroxide (BP) in aerated polymer films upon irradiation at >400 nm (i.e., the long-wavelength edge of the n→π* absorption band of BZ, where BP does not absorb). Here, we summarize results for the photoperoxidation of BZ structures with molecular oxygen, principally in glassy polymer matrices. Some of the polymers are doped directly with BZ or its derivatives, and others, contain covalently attached BZ pendant groups from which BP groups are derived. While the decomposition of low-molecular-weight BP doped into polymer films (such as those of polystyrene (PS)) results in a net decrease in polymer molecular weight, thermal decomposition of pendant BP groups is an efficient method for chain crosslinking. Crosslinking of PS films doped with a molecule containing two covalently linked BZ or BP groups proceeds in a similar fashion. Free radicals from the covalently attached BP allow grafting of new monomers, as well. Additionally, the use of radiation filtered through masks has been used to create patterns of polymers on solid surfaces. Crosslinking of photodegradable poly(phenyl vinyl ketone) with BP structures obtained by photoperoxidation of BZ structures for the preparation of photodegradable polymer networks is described as well. In sum, the use of BZ and BP and their derivatives offers simple and convenient routes for modifying polymer chains and, especially, for crosslinking them. Specific applications of each use and process are provided. Although applications with PS are featured here, the methodologies described are amenable to a wide variety of other polymers.
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Affiliation(s)
- Ivan Lukáč
- Polymer Institute, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 41 Bratislava, Slovakia; (B.H.); (M.D.)
- Correspondence: ; Tel.: +42-1944333672
| | - Branislav Husár
- Polymer Institute, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 41 Bratislava, Slovakia; (B.H.); (M.D.)
| | - Martin Danko
- Polymer Institute, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 41 Bratislava, Slovakia; (B.H.); (M.D.)
| | - Richard G. Weiss
- Department of Chemistry, Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, DC 20057, USA;
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Banerjee M, Panjikar PC, Bhutia ZT, Bhosle AA, Chatterjee A. Micellar nanoreactors for organic transformations with a focus on “dehydration” reactions in water: A decade update. Tetrahedron 2021. [DOI: 10.1016/j.tet.2021.132142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Liao CC, Hseu TH, Lin HS, Tang CP, Ueng YG, Wang JL, Wann GH, Wu KS. Synthesis and Photochemistry ofsyn- andanti-9,10-Epoxy-1, 4-dihydro-1,4-ethanonaphthalene-2,3-diones. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.199100044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Liao CC, Ueng YG. Photochemistry of Bicyclo[2.2.2]oct-5-Ene-2,3-Diones and Reactions of the Intermediates Bicyclo[4.2.0]oct-2-Ene-7,8-Diones. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.199300088] [Citation(s) in RCA: 3] [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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Liao CC, Lin HS, Tsai YF, Ueng YG. Photochemistry of Syn- and Anti-A8,9-Dimethoxycarbonyl-1,5-Dipropyl-3-Oxatricyclo[3.2.2.02,4]Non-8-Ene-6,7-Dione. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.199300079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Stunnenberg F, Cerfontain H, Geenevasen JAJ, Hielkema W. Photochemistry and spectroscopy of three α-oxo oxime ethers: 4-(methoxyimino)-2,2,3,3-tetramethylcyclobutanone, 3,3,5-trimethyl-4(5H)-isoxazolone and 6-(benzyloxyimino)-2,2,5,5-tetramethylcyclohexanone. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19911100202] [Citation(s) in RCA: 7] [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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de Lucas NC, Elias MM, Firme CL, Corrêa RJ, Garden SJ, Netto-Ferreira JC, Nicodem DE. A combined laser flash photolysis, density functional theory and atoms in molecules study of the photochemical hydrogen abstraction by pyrene-4,5-dione. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2008.08.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sequential Norrish Type II Photoelimination and Intramolecular Aldol Cyclization of 1,2-Diketones in Carbohydrate Systems: Stereoselective Synthesis of Cyclopentitols. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200803696] [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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Álvarez-Dorta D, León E, Kennedy A, Riesco-Fagundo C, Suárez E. Sequential Norrish Type II Photoelimination and Intramolecular Aldol Cyclization of 1,2-Diketones in Carbohydrate Systems: Stereoselective Synthesis of Cyclopentitols. Angew Chem Int Ed Engl 2008; 47:8917-9. [DOI: 10.1002/anie.200803696] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Synthesis, photoperoxidation and crosslinking of styrene copolymer with pendant benzil moieties. J Photochem Photobiol A Chem 2008. [DOI: 10.1016/j.jphotochem.2007.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Müller‐Bötticher H, Fessner W, Melder J, Prinzbach H, Gries S, Irngartinger H. Functionalized Enantiomerically Pure [1.1.1]‐, [2.1.1]‐, [2.2.1]‐, and [2.2.2]Triblattanes. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/cber.19931261018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Hermann Müller‐Bötticher
- Chemisches Laboratorium der Universität Freiburg i.Br., Institut für Organische Chemie und Biochemie, Albertstraße 21, D‐79104 Freiburg i.Br
| | - Wolf‐Dieter Fessner
- Chemisches Laboratorium der Universität Freiburg i.Br., Institut für Organische Chemie und Biochemie, Albertstraße 21, D‐79104 Freiburg i.Br
| | - Johann‐Peter Melder
- Chemisches Laboratorium der Universität Freiburg i.Br., Institut für Organische Chemie und Biochemie, Albertstraße 21, D‐79104 Freiburg i.Br
| | - Horst Prinzbach
- Chemisches Laboratorium der Universität Freiburg i.Br., Institut für Organische Chemie und Biochemie, Albertstraße 21, D‐79104 Freiburg i.Br
| | - Stefan Gries
- Organisch‐Chemisches Institut der Universität Heidelberg, Im Neuenheimer Feld 270, D‐69120 Heidelberg
| | - Hermann Irngartinger
- Organisch‐Chemisches Institut der Universität Heidelberg, Im Neuenheimer Feld 270, D‐69120 Heidelberg
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Gleiter R, Doerner T, Irngartinger H. On the Homoconjugation Between Donor and Acceptor Fragments. Synthesis and Properties of Bishomosquaric Acid Derivatives. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/jlac.199619960313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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15
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Photooxidation of benzil groups in the presence of hindered amine stabilizers in the polystyrene film. J Appl Polym Sci 2006. [DOI: 10.1002/app.23212] [Citation(s) in RCA: 5] [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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Yamada H, Yamashita Y, Kikuchi M, Watanabe H, Okujima T, Uno H, Ogawa T, Ohara K, Ono N. Photochemical Synthesis of Pentacene and its Derivatives. Chemistry 2005; 11:6212-20. [PMID: 16075447 DOI: 10.1002/chem.200500564] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A novel alpha-diketone precursor of pentacene, 6,13-dihydro-6,13-ethanopentacene-15,16-dione, was prepared and converted successfully to pentacene in 74 % yield by photolysis of the precursor in toluene: Irradiation of the diketone solution in toluene with light of 460 nm under an Ar atmosphere caused the solution to change from yellow to fluorescent orange-pink within a few minutes, after which, purple precipitates appeared. After 35 min, the solution changed to colorless and the purple precipitates were filtered to give pentacene in 74 % yield. By contrast, in the presence of oxygen, the color of the solution changed from yellow to pale yellow, and only 6,13-endoperoxide of pentacene was quantitatively obtained. The rate of the reaction upon photolysis was measured by observing the decay of n-pi* absorption of the precursor at 460 nm, and was found to be similar in both the presence and absence of oxygen. Therefore, the photoreaction of the alpha-diketone precursor seemed to occur via the singlet excited state. Because the T-T absorption of pentacene was observed upon photolysis of the precursor in the nanosecond transient absorption measurement under an Ar atmosphere, the excited triplet state of the pentacene generated singlet oxygen by sensitization, and it reacted with the ground-state pentacene to give the 6,13-endoperoxide. The alpha-diketone deposited on glass was also converted successfully to pentacene film by photoirradiation. In addition, diketone precursors of a mixture of 2,8- and 2,9-dibromopentacene and 2,6-trianthrylene were also prepared and their photoconversion was performed.
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Affiliation(s)
- Hiroko Yamada
- Department of Chemistry, Faculty of Science, Ehime University, Matsuyama, Japan.
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Togashi DM, Nicodem DE. Photophysical studies of 9,10-phenanthrenequinones. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:3205-12. [PMID: 15477165 DOI: 10.1016/j.saa.2004.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2003] [Accepted: 03/08/2004] [Indexed: 05/08/2023]
Abstract
The characterization of the excited states of 9,10-phenanthrenequinone (PQ) and its derivatives substituted in the 3 and 6 positions with methoxy (PQ1), chloro (PQ2), methyl (PQ3) and fluoro (PQ3) was carried out using steady-state UV-Visible absorption spectroscopy and phosphorescence emission spectroscopy at room temperature and at 77 K. Nanosecond laser flash photolysis was used to obtain the time resolved spectra from the triplet emission decays. The compounds presented phosphorescence in benzene, chlorobenzene and acetonitrile solutions at room temperature and at 77 K. The phosphorescence of the methoxy derivative, however, was observed only at low temperature. The derivatives showed a slightly higher triplet energy than PQ. The Hammett plots were applied to correlate singlet and triplet energies with sigma values that account for resonance and the radical character. It is observed that singlet and triplet energies increase with electron donating groups.
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Affiliation(s)
- Denisio M Togashi
- Instituto de Quimica, Universidade Federal do Rio de Janeiro, 21945-970, Brazil.
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Mosnáček J, Lukáč I, Chromik Š, Kostič I, Hrdlovič P. Network formation of a phenyl vinyl ketone copolymer with 4-vinylbenzil and its photodecrosslinking in films. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/pola.10860] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Smith TA, Lokan N, Cabral N, Davies SR, Paddon-Row MN, Ghiggino KP. Photophysics of novel donor–{saturated rigid hydrocarbon bridge}–acceptor systems exhibiting efficient excitation energy transfer. J Photochem Photobiol A Chem 2002. [DOI: 10.1016/s1010-6030(02)00003-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rubin MB, Kapon M. Photochemistry of bicyclo[2.2.2]Octene-2,3-dione. Intersystem crossing via an excimer. J Photochem Photobiol A Chem 1999. [DOI: 10.1016/s1010-6030(99)00066-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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Behr J, Braun R, Grimme S, Kummer M, Martin HD, Mayer B, Rubin MB, Ruck C. Multichromophoric Systems by Diels–Alder Reaction of Barrelene witho-Benzoquinones: Tetracyclo[6.2.2.23,6.02,7]tetradeca-9,11,13-triene-4,5-diones. European J Org Chem 1998. [DOI: 10.1002/(sici)1099-0690(199811)1998:11<2339::aid-ejoc2339>3.0.co;2-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Rubin MB, Etinger M, Kapon M, Krochmal EC, Monosov R, Wierlacher S, Sander W. Photochemistry of Diaryl Vicinal Tetraketones and Chemistry of Intermediate (Aroyloxy)arylketenes(1). J Org Chem 1998; 63:480-488. [PMID: 11672036 DOI: 10.1021/jo971247q] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photolysis of diaryl vic-tetraketones results in formation of tricyclic-gamma-lactones 3 and 4 with low quantum but high chemical yield. (Aroyloxy)arylketenes and carbon monoxide are the initial photochemical products of these photolyses. Subsequent reaction of ketene with ground-state tetraketone results in formation of the observed photoproducts via intermediate beta-lactones. The latter are formed with a high degree of stereoselectivity. The failure of a cyclic tetraketone to react is attributed to its inability to undergo the cyclic mechanism proposed for formation of ketenes from tetraketones. Dimesityl and di-tert-butyl tetraketones react by a competing intramolecular hydrogen atom transfer mechanism. Dimerization of (benzoyloxy)phenylketene and its reactions with a number of tetraketones are described.
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Affiliation(s)
- Mordecai B. Rubin
- Department of Chemistry, Technion - Israel Institute of Technology, Haifa, Israel and Institute für Organische Chemie, Hagenring 30, D-3300 Braunschweig, Germany
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Olovsson G, Scheffer JR, Trotter J, Wu CH. Novel differences between the solid state and solution phase photochemistry of 1,2-cyclodecanedione. Tetrahedron Lett 1997. [DOI: 10.1016/s0040-4039(97)01657-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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25
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Agosta WC, Margaretha P. Exploring the 1,5 Cyclization of Alkyl Propargyl 1,4 Biradicals. Acc Chem Res 1996. [DOI: 10.1021/ar9500325] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- William C. Agosta
- The Laboratories of The Rockefeller University, New York, New York 10021-6399, and Institut für Organische Chemie,
Universität Hamburg, D-20146 Hamburg, Germany
| | - Paul Margaretha
- The Laboratories of The Rockefeller University, New York, New York 10021-6399, and Institut für Organische Chemie,
Universität Hamburg, D-20146 Hamburg, Germany
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Mukherjee AK, Margaretha P, Agosta WC. Photoaddition of Alkenes to Conjugated α-Diketones: Tandem Cyclizations Leading to Tetrasubstituted Furans1a. J Org Chem 1996. [DOI: 10.1021/jo952079+] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Rubin MB, Heller M, Monisov R, Gleiter R, Doerner T. Photochemistry of vicinal triketones. J Photochem Photobiol A Chem 1995. [DOI: 10.1016/1010-6030(94)03969-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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28
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Lin YM, Ueng YG, Wu SN. Photolysis of (7R)-7-Methoxycarbonyl-1,5-di-f-butylbicyclo[2.2.2]oct-5-ene-2,3-dione at Various Temperatures. J CHIN CHEM SOC-TAIP 1995. [DOI: 10.1002/jccs.199500001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Mukherjee AK, Agosta WC. Tetrasubstituted furans from novel [3 + 2] photocycloaddition of conjugated acetylenic α-diketones with alkenes. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940001821] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Derivatives of 1,2-diketones; Emission spectra in polymer matrices and efficiency as initiators of degradation. Polym Degrad Stab 1994. [DOI: 10.1016/0141-3910(94)90069-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Behr J, Braun R, Martin HD, Steigel A, Rubin MB. Small and Medium Rings, 76. Photorearrangement of Polycyclic Quinoxalines, Isomerisations of Isodrin-Type and Aza-Di-π-Methane Chromophores. ACTA ACUST UNITED AC 1991. [DOI: 10.1002/cber.19911240422] [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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Al-Jalal N, Ijam M, Al-Omran F, Gopalakrishnan B. Photoaddition of furil and diethyloxalate to electron-rich olefins. J Photochem Photobiol A Chem 1991. [DOI: 10.1016/1010-6030(91)87036-u] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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The photoreaction between benzil and stilbene: a reinvestigation by gas chromatography—mass spectrometry. J Photochem Photobiol A Chem 1990. [DOI: 10.1016/1010-6030(90)80021-o] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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34
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Christl M, Kraft A. Tricyclo[3.1.0.02,6]hexandion (das Valen deso-Benzochinons), Bicyclo[2.1.1]hexan-2,3-dion und Valene eines Chinoxalins, des Phenazins sowie eines Benzophenazins. Angew Chem Int Ed Engl 1988. [DOI: 10.1002/ange.19881001036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mattay J, Gersdorf J, Buchkremer K. Photoreactions of biacetyl with electron-rich olefins. An extended mechanism. ACTA ACUST UNITED AC 1987. [DOI: 10.1002/cber.19871200310] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Tintel C, Terheijden J, Lugtenburg J, Cornelisse J. Photoreduction and photoaddition reactions of pyrenediones. Tetrahedron Lett 1987. [DOI: 10.1016/s0040-4039(00)96044-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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