Articles producció científica> Química Física i Inorgànica

Photosensitization versus Photocyclization: competitive reactions of phenylphenalenone in its role as phytoanticipins in plant defense strategies

  • Datos identificativos

    Identificador: imarina:3707868
    Autores:
    Josep CasellasMar Reguero
    Resumen:
    Phenalenone derivatives are involved in plant defense strategies, producing molecular singlet oxygen in a photosensitization process. Many experimental and theoretical studies determined that phenalenone (PN) can carry out this process with a quantum yield close to one. However, it has been observed that the efficiency of some of its derivatives is much lower. This is the case of 9-phenylphenalenone (9-PhPN). To elucidate the factors that determine the different photochemistry of PN and its derivate 9-PhPN, we have developed a CASSCF/CASPT2 study where several deactivation paths through the lowest excited states have been explored. We have found that the characteristics of the low-lying excited states are similar for both PN and 9-PhPN in the areas near the geometry of excitation. Consequently, the first processes that take place immediately after absorption are possible in both systems, including the population of the triplet state responsible for oxygen sensitization. However, 9-PhPN can also undergo cyclisation by a bond formation between the carbonyl oxygen and a carbon atom of the phenyl substituent. This process competes favourably with population of triplet states and is responsible for the decrease of the quantum yield of oxygen sensitization in 9-PhPN relative to PN.
  • Otros:

    Autor según el artículo: Josep Casellas; Mar Reguero
    Departamento: Química Física i Inorgànica
    Autor/es de la URV: Reguero de la Poza, Maria del Mar
    Palabras clave: Mecanismes de reacció Fotoquímica
    Resumen: Phenalenone derivatives are involved in plant defense strategies, producing molecular singlet oxygen in a photosensitization process. Many experimental and theoretical studies determined that phenalenone (PN) can carry out this process with a quantum yield close to one. However, it has been observed that the efficiency of some of its derivatives is much lower. This is the case of 9-phenylphenalenone (9-PhPN). To elucidate the factors that determine the different photochemistry of PN and its derivate 9-PhPN, we have developed a CASSCF/CASPT2 study where several deactivation paths through the lowest excited states have been explored. We have found that the characteristics of the low-lying excited states are similar for both PN and 9-PhPN in the areas near the geometry of excitation. Consequently, the first processes that take place immediately after absorption are possible in both systems, including the population of the triplet state responsible for oxygen sensitization. However, 9-PhPN can also undergo cyclisation by a bond formation between the carbonyl oxygen and a carbon atom of the phenyl substituent. This process competes favourably with population of triplet states and is responsible for the decrease of the quantum yield of oxygen sensitization in 9-PhPN relative to PN.
    Áreas temáticas: Química Physics, atomic, molecular & chemical Physical and theoretical chemistry Odontología Medicine (miscellaneous) Medicina ii Medicina i Materiais Interdisciplinar Geociências General medicine Farmacia Ensino Engenharias iv Engenharias iii Engenharias ii Ciências biológicas ii Ciências biológicas i Ciências ambientais Ciências agrárias i Chemistry, physical Biotecnología Biodiversidade Astronomia / física
    Acceso a la licencia de uso: https://creativecommons.org/licenses/by/3.0/es/
    ISSN: 15205215
    Direcció de correo del autor: mar.reguero@urv.cat
    Identificador del autor: 0000-0001-9668-8265
    Página final: 821
    Fecha de alta del registro: 2024-09-07
    Volumen de revista: 122
    Versión del articulo depositado: info:eu-repo/semantics/submittedVersion
    Enlace a la fuente original: https://pubs.acs.org/doi/10.1021/acs.jpca.7b11569
    URL Documento de licencia: https://repositori.urv.cat/ca/proteccio-de-dades/
    Referencia al articulo segun fuente origial: Journal Of Physical Chemistry a. 122 (3): 811-821
    Referencia de l'ítem segons les normes APA: Josep Casellas; Mar Reguero (2018). Photosensitization versus Photocyclization: competitive reactions of phenylphenalenone in its role as phytoanticipins in plant defense strategies. Journal Of Physical Chemistry a, 122(3), 811-821. DOI: 10.1021/acs.jpca.7b11569
    DOI del artículo: 10.1021/acs.jpca.7b11569
    Entidad: Universitat Rovira i Virgili
    Año de publicación de la revista: 2018
    Página inicial: 811
    Tipo de publicación: Journal Publications
  • Palabras clave:

    Chemistry, Physical,Medicine (Miscellaneous),Physical and Theoretical Chemistry,Physics, Atomic, Molecular & Chemical
    Mecanismes de reacció
    Fotoquímica
    Química
    Physics, atomic, molecular & chemical
    Physical and theoretical chemistry
    Odontología
    Medicine (miscellaneous)
    Medicina ii
    Medicina i
    Materiais
    Interdisciplinar
    Geociências
    General medicine
    Farmacia
    Ensino
    Engenharias iv
    Engenharias iii
    Engenharias ii
    Ciências biológicas ii
    Ciências biológicas i
    Ciências ambientais
    Ciências agrárias i
    Chemistry, physical
    Biotecnología
    Biodiversidade
    Astronomia / física
  • Documentos:

  • Cerca a google

    Search to google scholar