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
- Institución
- Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
- OAI Identificador
- tesis:tesis_n2831_Biondic
Ver los metadatos del registro completo
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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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13.070432 |