Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas

Autores
Biondic, Miriana Carla
Año de publicación
1996
Idioma
español castellano
Tipo de recurso
tesis doctoral
Estado
versión publicada
Colaborador/a o director/a de tesis
Erra Balsells, Rosa
Descripción
In this work the photochemical behavior of full aromatic b-carbolines (nor-harmane, harmane, harmine and harmol) and two 3,4-dihydro b-carbolines (harmaline and harmalol) was studied. For the first time the UV absorption, emission and excitation spectra in organic solutions were described as well as on solid supports (silica gel, paper) and on powdered sample. The K of the complexation equilibrium between the full aromatic b-carbolines with alcohols forming a 1:2 adducts were measured and the pKa and pKa* in acetonitrile were determined by means of electronic absorption and fluorescence spectroscopy. Considering that these compounds are markedly fluorescent their behavior in the presence of CCl4 and other halomethanes (CH2Cl2, CHCl3, CH2BrCH2Br, CHBr3 and CBr4) which act as quenchers using either EtOH, iso-PrOH or MeCN as solvents was studied. We concluded that this quenching is dynamic and may take place through the formation of an exciplex followed by an electron transfer from the excited b-carboline to the halogenated compound starting the photochemical reaction. When a solution of either of these alkaloids (10-3 M) was irradiated in the presence of CCl4 in a protic organic solvent, the main product obtained, with more than 98% yield, was the hydrochloride. Besides, the gc-MS analysis showed traces of carboalcoxy and chloro-derivatives.%The feasibility of an exciton or a photon single electron transfer mechanism is discussed and parameters such as DGote, Ksv, kq, DG‡, DG‡(0), l, and E0ox were calculated using the Rehm-Weller, Marcus and Stern-Volmer models.%The quantum yield of photobleaching in different solvents was determined relative to the disappearance of harmane in EtOH-CCl4, which in turn was determined using potassium ferrioxalate as actinometer.
Fil: Biondic, Miriana Carla. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Materia
SS-CARBOLINAS
FOTOQUIMICA DE SS-CARBOLINAS
SS-CARBOLINAS-TETRACLORURO DE CARBONO
EQUILIBRIO ACIDO-BASE DE SS-CARBOLINAS
ESPECTROS ELECTRONICOS DE SS-CARBOLINAS
SS-CARBOLINES
SS-CARBOLINES-PHOTOCHEMISTRY
SS-CARBOLINES-CARBON-TETRACHLORIDE
SS-CARBOLINES-ACID-BASE EQUILIBRIUM
SS-CARBOLINES-ELECTRONIC SPECTRA
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar
Repositorio
Biblioteca Digital (UBA-FCEN)
Institución
Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
OAI Identificador
tesis:tesis_n2831_Biondic

id BDUBAFCEN_92227b146301054d1196a51a295ea1b7
oai_identifier_str tesis:tesis_n2831_Biondic
network_acronym_str BDUBAFCEN
repository_id_str 1896
network_name_str Biblioteca Digital (UBA-FCEN)
spelling Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidasPhotochemistry of ß-carbolines in diluted organic solutionsBiondic, Miriana CarlaSS-CARBOLINASFOTOQUIMICA DE SS-CARBOLINASSS-CARBOLINAS-TETRACLORURO DE CARBONOEQUILIBRIO ACIDO-BASE DE SS-CARBOLINASESPECTROS ELECTRONICOS DE SS-CARBOLINASSS-CARBOLINESSS-CARBOLINES-PHOTOCHEMISTRYSS-CARBOLINES-CARBON-TETRACHLORIDESS-CARBOLINES-ACID-BASE EQUILIBRIUMSS-CARBOLINES-ELECTRONIC SPECTRAIn this work the photochemical behavior of full aromatic b-carbolines (nor-harmane, harmane, harmine and harmol) and two 3,4-dihydro b-carbolines (harmaline and harmalol) was studied. For the first time the UV absorption, emission and excitation spectra in organic solutions were described as well as on solid supports (silica gel, paper) and on powdered sample. The K of the complexation equilibrium between the full aromatic b-carbolines with alcohols forming a 1:2 adducts were measured and the pKa and pKa* in acetonitrile were determined by means of electronic absorption and fluorescence spectroscopy. Considering that these compounds are markedly fluorescent their behavior in the presence of CCl4 and other halomethanes (CH2Cl2, CHCl3, CH2BrCH2Br, CHBr3 and CBr4) which act as quenchers using either EtOH, iso-PrOH or MeCN as solvents was studied. We concluded that this quenching is dynamic and may take place through the formation of an exciplex followed by an electron transfer from the excited b-carboline to the halogenated compound starting the photochemical reaction. When a solution of either of these alkaloids (10-3 M) was irradiated in the presence of CCl4 in a protic organic solvent, the main product obtained, with more than 98% yield, was the hydrochloride. Besides, the gc-MS analysis showed traces of carboalcoxy and chloro-derivatives.%The feasibility of an exciton or a photon single electron transfer mechanism is discussed and parameters such as DGote, Ksv, kq, DG‡, DG‡(0), l, and E0ox were calculated using the Rehm-Weller, Marcus and Stern-Volmer models.%The quantum yield of photobleaching in different solvents was determined relative to the disappearance of harmane in EtOH-CCl4, which in turn was determined using potassium ferrioxalate as actinometer.Fil: Biondic, Miriana Carla. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Universidad de Buenos Aires. Facultad de Ciencias Exactas y NaturalesErra Balsells, Rosa1996info:eu-repo/semantics/doctoralThesisinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_db06info:ar-repo/semantics/tesisDoctoralapplication/pdfhttps://hdl.handle.net/20.500.12110/tesis_n2831_Biondicspainfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/arreponame:Biblioteca Digital (UBA-FCEN)instname:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturalesinstacron:UBA-FCEN2025-09-29T13:42:39Ztesis:tesis_n2831_BiondicInstitucionalhttps://digital.bl.fcen.uba.ar/Universidad públicaNo correspondehttps://digital.bl.fcen.uba.ar/cgi-bin/oaiserver.cgiana@bl.fcen.uba.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:18962025-09-29 13:42:39.982Biblioteca Digital (UBA-FCEN) - Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturalesfalse
dc.title.none.fl_str_mv Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
Photochemistry of ß-carbolines in diluted organic solutions
title Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
spellingShingle Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
Biondic, Miriana Carla
SS-CARBOLINAS
FOTOQUIMICA DE SS-CARBOLINAS
SS-CARBOLINAS-TETRACLORURO DE CARBONO
EQUILIBRIO ACIDO-BASE DE SS-CARBOLINAS
ESPECTROS ELECTRONICOS DE SS-CARBOLINAS
SS-CARBOLINES
SS-CARBOLINES-PHOTOCHEMISTRY
SS-CARBOLINES-CARBON-TETRACHLORIDE
SS-CARBOLINES-ACID-BASE EQUILIBRIUM
SS-CARBOLINES-ELECTRONIC SPECTRA
title_short Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
title_full Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
title_fullStr Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
title_full_unstemmed Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
title_sort Fotoquímica de ß-Carbolinas en soluciones orgánicas diluidas
dc.creator.none.fl_str_mv Biondic, Miriana Carla
author Biondic, Miriana Carla
author_facet Biondic, Miriana Carla
author_role author
dc.contributor.none.fl_str_mv Erra Balsells, Rosa
dc.subject.none.fl_str_mv SS-CARBOLINAS
FOTOQUIMICA DE SS-CARBOLINAS
SS-CARBOLINAS-TETRACLORURO DE CARBONO
EQUILIBRIO ACIDO-BASE DE SS-CARBOLINAS
ESPECTROS ELECTRONICOS DE SS-CARBOLINAS
SS-CARBOLINES
SS-CARBOLINES-PHOTOCHEMISTRY
SS-CARBOLINES-CARBON-TETRACHLORIDE
SS-CARBOLINES-ACID-BASE EQUILIBRIUM
SS-CARBOLINES-ELECTRONIC SPECTRA
topic SS-CARBOLINAS
FOTOQUIMICA DE SS-CARBOLINAS
SS-CARBOLINAS-TETRACLORURO DE CARBONO
EQUILIBRIO ACIDO-BASE DE SS-CARBOLINAS
ESPECTROS ELECTRONICOS DE SS-CARBOLINAS
SS-CARBOLINES
SS-CARBOLINES-PHOTOCHEMISTRY
SS-CARBOLINES-CARBON-TETRACHLORIDE
SS-CARBOLINES-ACID-BASE EQUILIBRIUM
SS-CARBOLINES-ELECTRONIC SPECTRA
dc.description.none.fl_txt_mv In this work the photochemical behavior of full aromatic b-carbolines (nor-harmane, harmane, harmine and harmol) and two 3,4-dihydro b-carbolines (harmaline and harmalol) was studied. For the first time the UV absorption, emission and excitation spectra in organic solutions were described as well as on solid supports (silica gel, paper) and on powdered sample. The K of the complexation equilibrium between the full aromatic b-carbolines with alcohols forming a 1:2 adducts were measured and the pKa and pKa* in acetonitrile were determined by means of electronic absorption and fluorescence spectroscopy. Considering that these compounds are markedly fluorescent their behavior in the presence of CCl4 and other halomethanes (CH2Cl2, CHCl3, CH2BrCH2Br, CHBr3 and CBr4) which act as quenchers using either EtOH, iso-PrOH or MeCN as solvents was studied. We concluded that this quenching is dynamic and may take place through the formation of an exciplex followed by an electron transfer from the excited b-carboline to the halogenated compound starting the photochemical reaction. When a solution of either of these alkaloids (10-3 M) was irradiated in the presence of CCl4 in a protic organic solvent, the main product obtained, with more than 98% yield, was the hydrochloride. Besides, the gc-MS analysis showed traces of carboalcoxy and chloro-derivatives.%The feasibility of an exciton or a photon single electron transfer mechanism is discussed and parameters such as DGote, Ksv, kq, DG‡, DG‡(0), l, and E0ox were calculated using the Rehm-Weller, Marcus and Stern-Volmer models.%The quantum yield of photobleaching in different solvents was determined relative to the disappearance of harmane in EtOH-CCl4, which in turn was determined using potassium ferrioxalate as actinometer.
Fil: Biondic, Miriana Carla. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
description In this work the photochemical behavior of full aromatic b-carbolines (nor-harmane, harmane, harmine and harmol) and two 3,4-dihydro b-carbolines (harmaline and harmalol) was studied. For the first time the UV absorption, emission and excitation spectra in organic solutions were described as well as on solid supports (silica gel, paper) and on powdered sample. The K of the complexation equilibrium between the full aromatic b-carbolines with alcohols forming a 1:2 adducts were measured and the pKa and pKa* in acetonitrile were determined by means of electronic absorption and fluorescence spectroscopy. Considering that these compounds are markedly fluorescent their behavior in the presence of CCl4 and other halomethanes (CH2Cl2, CHCl3, CH2BrCH2Br, CHBr3 and CBr4) which act as quenchers using either EtOH, iso-PrOH or MeCN as solvents was studied. We concluded that this quenching is dynamic and may take place through the formation of an exciplex followed by an electron transfer from the excited b-carboline to the halogenated compound starting the photochemical reaction. When a solution of either of these alkaloids (10-3 M) was irradiated in the presence of CCl4 in a protic organic solvent, the main product obtained, with more than 98% yield, was the hydrochloride. Besides, the gc-MS analysis showed traces of carboalcoxy and chloro-derivatives.%The feasibility of an exciton or a photon single electron transfer mechanism is discussed and parameters such as DGote, Ksv, kq, DG‡, DG‡(0), l, and E0ox were calculated using the Rehm-Weller, Marcus and Stern-Volmer models.%The quantum yield of photobleaching in different solvents was determined relative to the disappearance of harmane in EtOH-CCl4, which in turn was determined using potassium ferrioxalate as actinometer.
publishDate 1996
dc.date.none.fl_str_mv 1996
dc.type.none.fl_str_mv info:eu-repo/semantics/doctoralThesis
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_db06
info:ar-repo/semantics/tesisDoctoral
format doctoralThesis
status_str publishedVersion
dc.identifier.none.fl_str_mv https://hdl.handle.net/20.500.12110/tesis_n2831_Biondic
url https://hdl.handle.net/20.500.12110/tesis_n2831_Biondic
dc.language.none.fl_str_mv spa
language spa
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales
publisher.none.fl_str_mv Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales
dc.source.none.fl_str_mv reponame:Biblioteca Digital (UBA-FCEN)
instname:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
instacron:UBA-FCEN
reponame_str Biblioteca Digital (UBA-FCEN)
collection Biblioteca Digital (UBA-FCEN)
instname_str Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
instacron_str UBA-FCEN
institution UBA-FCEN
repository.name.fl_str_mv Biblioteca Digital (UBA-FCEN) - Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
repository.mail.fl_str_mv ana@bl.fcen.uba.ar
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