LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 233

Search options

  1. Article ; Online: Phenacyl Bromide as a Single-Component Photoinitiator: Photoinduced Step-Growth Polymerization of N-Methylpyrrole and N-Methylindole.

    Kocaarslan, Azra / Kaya, Kerem / Jockusch, Steffen / Yagci, Yusuf

    Angewandte Chemie (International ed. in English)

    2022  Volume 61, Issue 36, Page(s) e202208845

    Abstract: The synthesis of step-growth polymers by photoinduced methods is a challenging issue in synthetic chemistry. Here, we report a single component near UV responsive photopolymerization system for step-growth polymerization of N-methylpyrrole (MPyr) and N- ... ...

    Abstract The synthesis of step-growth polymers by photoinduced methods is a challenging issue in synthetic chemistry. Here, we report a single component near UV responsive photopolymerization system for step-growth polymerization of N-methylpyrrole (MPyr) and N-methylindole (MIn) by using phenacyl bromide (PAB). The obtained high molecular weight conjugated polymers were characterized by spectral and chromatographic methods. Detailed laser flash photolysis and spectroscopic studies revealed that polymerization proceeds by successive photoinduced cleavage of PAB followed by electron transfer, proton release and coupling processes. After photolysis, chain growth continues also in daylight or dark by acidic oxidation. The structural features of the polymers were investigated. PAB single component photoinitiator enables an efficient, rapid, room temperature step-growth polymerization process of MPyr and MIn that can be applied to other conjugated monomers.
    MeSH term(s) Acetophenones ; Polymerization ; Polymers/chemistry ; Pyrroles
    Chemical Substances Acetophenones ; Polymers ; Pyrroles ; phenacyl bromide (754Y0U325I) ; N-methylpyrrole (NG5GPN98ZG)
    Language English
    Publishing date 2022-07-25
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202208845
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  2. Article ; Online: The red chlorophyll catabolite (RCC) is an inefficient sensitizer of singlet oxygen - photochemical studies of the methyl ester of RCC.

    Jockusch, Steffen / Kräutler, Bernhard

    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology

    2020  Volume 19, Issue 5, Page(s) 668–673

    Abstract: The red chlorophyll catabolite (RCC) is a proposed cryptic intermediate of chlorophyll (Chl) breakdown in higher plants. Its accumulation in higher plants is believed to be metabolically suppressed, as RCC is commonly suspected to efficiently sensitize ... ...

    Abstract The red chlorophyll catabolite (RCC) is a proposed cryptic intermediate of chlorophyll (Chl) breakdown in higher plants. Its accumulation in higher plants is believed to be metabolically suppressed, as RCC is commonly suspected to efficiently sensitize for the formation of the cell poison singlet oxygen (
    MeSH term(s) Chlorophyll/chemistry ; Esters/chemistry ; Luminescence ; Molecular Structure ; Photochemical Processes ; Singlet Oxygen/chemistry ; Spectrometry, Fluorescence
    Chemical Substances Esters ; Chlorophyll (1406-65-1) ; Singlet Oxygen (17778-80-2)
    Language English
    Publishing date 2020-04-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2072584-X
    ISSN 1474-9092 ; 1474-905X
    ISSN (online) 1474-9092
    ISSN 1474-905X
    DOI 10.1039/d0pp00071j
    Database MEDical Literature Analysis and Retrieval System OnLINE

    Full text online

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  3. Article ; Online: Thioxanthone Dioxide Triplet States Have Low Oxygen Quenching Rate Constants.

    Jockusch, Steffen / Kazancioglu, Elif Ozcelik / Karaca, Nurcan / Arsu, Nergis / Landgraf, Stephan / Ogilby, Peter R

    The journal of physical chemistry. B

    2023  Volume 128, Issue 1, Page(s) 244–249

    Abstract: With few exceptions, triplet excited states of organic molecules, ...

    Abstract With few exceptions, triplet excited states of organic molecules,
    Language English
    Publishing date 2023-12-27
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5207
    ISSN (online) 1520-5207
    DOI 10.1021/acs.jpcb.3c06077
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  4. Article ; Online: Chemoselective light-induced reactivity of β-enaminones.

    Valloli, Lakshmy Kannadi / Manal, Kavyasree / Lewis, Brieanna / Jockusch, Steffen / Sivaguru, Jayaraman

    Photochemistry and photobiology

    2023  

    Abstract: The irradiation of β-enaminones, generated in situ from cyclic 1,3-diketones and activated alkenes leads to polyheterocyclic skeletons. The photoproduct chemoselectivity depends on the type of cyclic 1,3-diketones employed viz., 2-acetylcyclopentanone ... ...

    Abstract The irradiation of β-enaminones, generated in situ from cyclic 1,3-diketones and activated alkenes leads to polyheterocyclic skeletons. The photoproduct chemoselectivity depends on the type of cyclic 1,3-diketones employed viz., 2-acetylcyclopentanone and 2-acetylcyclohexanone. The observed chemoselectivity was rationalized based on the Dieckmann-Kon rule.
    Language English
    Publishing date 2023-11-27
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123540-0
    ISSN 1751-1097 ; 0031-8655
    ISSN (online) 1751-1097
    ISSN 0031-8655
    DOI 10.1111/php.13889
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.B 1686: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  5. Article ; Online: Uncovering New Excited State Photochemical Reactivity by Altering the Course of the De Mayo Reaction.

    Kandappa, Sunil Kumar / Valloli, Lakshmy Kannadi / Jockusch, Steffen / Sivaguru, Jayaraman

    Journal of the American Chemical Society

    2021  Volume 143, Issue 10, Page(s) 3677–3681

    Abstract: An unprecedented and previously unknown photochemical reactivity of 1,3-dicarbonyl compounds is observed with amino-alkenes leading to dihydropyrans. This novel photochemical reactivity changes the established paradigm related to the De Mayo reaction ... ...

    Abstract An unprecedented and previously unknown photochemical reactivity of 1,3-dicarbonyl compounds is observed with amino-alkenes leading to dihydropyrans. This novel photochemical reactivity changes the established paradigm related to the De Mayo reaction between 1,3-dicarbonyl compounds and alkenes. This new reaction allows convenient access to the Marmycin core in a single step from commercially available reactants. The origin and scope of this new photoreaction is detailed with preliminary photophysical and mechanistic investigations.
    Language English
    Publishing date 2021-03-03
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.0c12099
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 55/32: Show issues
    Z 7.3: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article ; Online: Modulating Photochemical Properties to Enhance the Stability of Electronically Dimmable Eye Protection Devices

    Baburaj, Sruthy / Parthiban, Jayachandran / Rakhimov, Sarvar Aminovich / Johnson, Rasheedah / Sukhomlinova, Ludmila / Luchette, Paul / Jockusch, Steffen / Forbes, Malcolm D E / Sivaguru, Jayaraman

    Photochemistry and photobiology

    2023  Volume 99, Issue 3, Page(s) 901–905

    Abstract: The study evaluates compatibility of stabilizers with dye doped liquid crystal (LC) scaffolds that are used in electronically dimmable materials. The photodegradation of the materials was investigated and suitable stabilizers were evaluated to slow the ... ...

    Abstract The study evaluates compatibility of stabilizers with dye doped liquid crystal (LC) scaffolds that are used in electronically dimmable materials. The photodegradation of the materials was investigated and suitable stabilizers were evaluated to slow the degradation process. Various types of benzotriazole-based stabilizers were evaluated for stabilizing the liquid crystals. Based on spin trapping experiments, radicals generated upon UV exposure is likely responsible for the degradation of the system. The radical generation is competitively inhibited by the addition of stabilizers.
    Language English
    Publishing date 2023-03-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123540-0
    ISSN 1751-1097 ; 0031-8655
    ISSN (online) 1751-1097
    ISSN 0031-8655
    DOI 10.1111/php.13795
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Cologne/Königswinter

    Zs.B 1686: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  7. Article ; Online: Photochemical [2+4]-Dimerization Reaction from the Excited State.

    Ahuja, Sapna / Baburaj, Sruthy / Valloli, Lakshmy Kannadi / Rakhimov, Sarvar Aminovich / Manal, Kavyasree / Kushwaha, Aakrati / Jockusch, Steffen / Forbes, Malcolm D E / Sivaguru, Jayaraman

    Angewandte Chemie (International ed. in English)

    2023  Volume 63, Issue 4, Page(s) e202316662

    Abstract: Aryl-maleimides undergo a novel [2+4]-photodimerization instead of the expected [2+2]-photodimerization under both direct irradiation with visible light and under sensitized energy transfer conditions. This new excited state reactivity in aryl-maleimides ...

    Abstract Aryl-maleimides undergo a novel [2+4]-photodimerization instead of the expected [2+2]-photodimerization under both direct irradiation with visible light and under sensitized energy transfer conditions. This new excited state reactivity in aryl-maleimides is deciphered through photochemical, photophysical, and spectroscopic studies. The stereochemistry of the photodimer depends on the type of non-bonding interactions prevalent during photodimerization which is in turn dictated by the substituents on the maleimide ring. More importantly, the stereochemistry of the photodimer formed is complementary to the product observed under thermal conditions.
    Language English
    Publishing date 2023-12-20
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202316662
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  8. Article ; Online: Unraveling the Photophysical Characteristics, Aromaticity, and Stability of π-Extended Acene-Quinodimethyl Thioamides†.

    Yang, Guang / Yun, Young Ju / Peccati, Francesca / Jamhawi, Abdelqader M / Kamatham, Nareshbabu / Jockusch, Steffen / Jiménez-Osés, Gonzalo / Ayitou, A Jean-Luc

    Chemphyschem : a European journal of chemical physics and physical chemistry

    2023  Volume 24, Issue 21, Page(s) e202200906

    Abstract: Poly-aromatic systems that contain quinodimethyl (QDM) units are appealing for several photonic and spintronic applications owing to the unique electronic structure, aromaticity, and spin state(s) of the QDM ring. Herein, we report the synthesis and ... ...

    Abstract Poly-aromatic systems that contain quinodimethyl (QDM) units are appealing for several photonic and spintronic applications owing to the unique electronic structure, aromaticity, and spin state(s) of the QDM ring. Herein, we report the synthesis and characterization of novel QDM-based chromophores 1-3, which exhibit unique photo-excited behavior and aromaticity. Extending the aromatic core with a biphenyl/phenanthryl- and a pyrrolo-fragment led to reducing the optoelectronic bandgap and modulating the photophysics QDM 1-3. Yet, QDM 2 and 3 suffer from "aromaticity imbalance" and become relatively unstable compared to the parent compound QDM 1. Further assessment of local aromaticity using computational tools revealed that the pseudo-quinoidal ring B is the main driving force allowing to easily populate the excited triplet state of these chromophores. The present study provides complementary guidelines for designing novel non-classical poly-aromatic systems.
    Language English
    Publishing date 2023-09-19
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2025223-7
    ISSN 1439-7641 ; 1439-4235
    ISSN (online) 1439-7641
    ISSN 1439-4235
    DOI 10.1002/cphc.202200906
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

  9. Article ; Online: Comment on A. Tiessen "The fluorescent blue glow of banana fruits is not due to symplasmic plastidial catabolism but arises from insoluble phenols estherified to the cell wall".

    Kräutler, Bernhard / Müller, Thomas / Jockusch, Steffen

    Plant science : an international journal of experimental plant biology

    2019  Volume 280, Page(s) 461–462

    MeSH term(s) Cell Wall ; Color ; Fruit ; Musa ; Phenols
    Chemical Substances Phenols
    Language English
    Publishing date 2019-01-03
    Publishing country Ireland
    Document type Letter ; Comment
    ZDB-ID 742010-9
    ISSN 1873-2259 ; 0168-9452
    ISSN (online) 1873-2259
    ISSN 0168-9452
    DOI 10.1016/j.plantsci.2018.12.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 77/717: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  10. Article: Mussel-Inspired Coatings by Photoinduced Electron-Transfer Reactions: Photopolymerization of Dopamine under UV, Visible, and Daylight under Oxygen-Free Conditions

    Kaya, Kerem / Jockusch, Steffen / Yagci, Yusuf

    Macromolecules. 2021 June 23, v. 54, no. 13

    2021  

    Abstract: Photoinduced electron-transfer (PET) reactions represent a powerful methodology with widespread applications in the fields of organic and synthetic polymer chemistry. Within this literature, among the various surface coating methods, marine mussel- ... ...

    Abstract Photoinduced electron-transfer (PET) reactions represent a powerful methodology with widespread applications in the fields of organic and synthetic polymer chemistry. Within this literature, among the various surface coating methods, marine mussel-inspired adhesive bonding by polydopamine (PDA) coatings has attracted great interest. Although various procedures for PDA synthesis have been reported, they exhibit some limitations, such as requirement of acidic or basic conditions or strong oxidants. To address these issues, here we report a simple PET protocol for PDA production under UV, visible, and daylight irradiation using diphenyliodonium salt in the presence and absence of sensitizers. This new methodology provides future directions for surface coatings and bio-functionalization.
    Keywords dopamine ; electron transfer ; irradiation ; methodology ; polymers ; solar radiation
    Language English
    Dates of publication 2021-0623
    Size p. 5991-5999.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 1491942-4
    ISSN 1520-5835 ; 0024-9297
    ISSN (online) 1520-5835
    ISSN 0024-9297
    DOI 10.1021/acs.macromol.1c00946
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

To top