Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone

Detalhes bibliográficos
Autor(a) principal: De Oliveira, Edimar
Data de Publicação: 2006
Outros Autores: Torres, Jocilene D., Silva, Carlos C., Luz, Afrânio A. M., Bakuzis, Peter, Prado, Alexandre G. S.
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UnB
Texto Completo: http://repositorio.unb.br/handle/10482/26711
https://dx.doi.org/10.1590/S0103-50532006000500026
Resumo: A catalyst based on silica chemically modified with tetramethylguanidine (TMG) was synthesized by the co-condensation of tetraethylorthosilicate (TEOS) with a new silylant agent derived from the reaction between the TMG molecule and (3-chloropropyl)trimethoxysilane. A neutral n-dodecylamine template was used to organize the polymerization of the inorganic-organic catalyst. Thermogravimetry showed that the number of active pendant groups in the catalyst was 1.35 mmol g-1, with a surface area of 811 ± 75 m² g-1. Infrared spectroscopy and 13C and 29Si nuclear magnetic resonance data are in agreement with the proposed structure. This material has been used to catalyse the addition of nitromethane to cyclopentenone. The catalytic efficiency was followed and the nitromethylcyclopentanone conversion presented a yield of 98% at 3 h of reaction. The catalyst was recovered and reused 14 times, maintaining about 98% of its catalytic efficiency.
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spelling Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenoneSílicaTetrametilguanidinaAdição de MichaelNitroalcanoA catalyst based on silica chemically modified with tetramethylguanidine (TMG) was synthesized by the co-condensation of tetraethylorthosilicate (TEOS) with a new silylant agent derived from the reaction between the TMG molecule and (3-chloropropyl)trimethoxysilane. A neutral n-dodecylamine template was used to organize the polymerization of the inorganic-organic catalyst. Thermogravimetry showed that the number of active pendant groups in the catalyst was 1.35 mmol g-1, with a surface area of 811 ± 75 m² g-1. Infrared spectroscopy and 13C and 29Si nuclear magnetic resonance data are in agreement with the proposed structure. This material has been used to catalyse the addition of nitromethane to cyclopentenone. The catalytic efficiency was followed and the nitromethylcyclopentanone conversion presented a yield of 98% at 3 h of reaction. The catalyst was recovered and reused 14 times, maintaining about 98% of its catalytic efficiency.Um catalisador baseado em sílica quimicamente modificada com tetrametilguanidina (TMG) foi sintetizado pela co-condensação de tetraetilortossilicato (TEOS) com um novo agente sililante, preparado pela reação entre a molécula TMG e (3-cloropropil)trimetoxisilano. O direcionador n-dodecilamina foi utilizado para organizar a polimerização do catalisador inorgânico-orgânico. A termogravimetria mostrou que o número de sítios ativos do catalisador foi de 1,35 mmol g-1, com uma área superficial de 811 ± 75 m² g-1. A espectroscopia na região do infravermelho e de ressonância magnética nuclear no estado sólido para os núcleos 29Si e 13C confirmou a obtenção do produto desejado. Este material foi usado para catalisar a adição de nitrometano em ciclopentenona. 98% de conversão foi observada depois de 3 h de reação. O catalisador foi recuperado e reutilizado por mais catorze vezes, mantendo uma eficiência catalítica em torno de 98%.Em processamentoSociedade Brasileira de Química2017-12-07T04:45:02Z2017-12-07T04:45:02Z2006info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfJ. Braz. Chem. Soc.,v.17,n.5,p.994-999,2006http://repositorio.unb.br/handle/10482/26711https://dx.doi.org/10.1590/S0103-50532006000500026De Oliveira, EdimarTorres, Jocilene D.Silva, Carlos C.Luz, Afrânio A. M.Bakuzis, PeterPrado, Alexandre G. S.info:eu-repo/semantics/openAccessengreponame:Repositório Institucional da UnBinstname:Universidade de Brasília (UnB)instacron:UNB2024-08-28T19:04:10Zoai:repositorio.unb.br:10482/26711Repositório InstitucionalPUBhttps://repositorio.unb.br/oai/requestrepositorio@unb.bropendoar:2024-08-28T19:04:10Repositório Institucional da UnB - Universidade de Brasília (UnB)false
dc.title.none.fl_str_mv Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
title Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
spellingShingle Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
De Oliveira, Edimar
Sílica
Tetrametilguanidina
Adição de Michael
Nitroalcano
title_short Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
title_full Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
title_fullStr Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
title_full_unstemmed Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
title_sort Tetramethylguanidine covalently bonded onto silica gel as catalyst for the addition of nitromethane to cyclopentenone
author De Oliveira, Edimar
author_facet De Oliveira, Edimar
Torres, Jocilene D.
Silva, Carlos C.
Luz, Afrânio A. M.
Bakuzis, Peter
Prado, Alexandre G. S.
author_role author
author2 Torres, Jocilene D.
Silva, Carlos C.
Luz, Afrânio A. M.
Bakuzis, Peter
Prado, Alexandre G. S.
author2_role author
author
author
author
author
dc.contributor.author.fl_str_mv De Oliveira, Edimar
Torres, Jocilene D.
Silva, Carlos C.
Luz, Afrânio A. M.
Bakuzis, Peter
Prado, Alexandre G. S.
dc.subject.por.fl_str_mv Sílica
Tetrametilguanidina
Adição de Michael
Nitroalcano
topic Sílica
Tetrametilguanidina
Adição de Michael
Nitroalcano
description A catalyst based on silica chemically modified with tetramethylguanidine (TMG) was synthesized by the co-condensation of tetraethylorthosilicate (TEOS) with a new silylant agent derived from the reaction between the TMG molecule and (3-chloropropyl)trimethoxysilane. A neutral n-dodecylamine template was used to organize the polymerization of the inorganic-organic catalyst. Thermogravimetry showed that the number of active pendant groups in the catalyst was 1.35 mmol g-1, with a surface area of 811 ± 75 m² g-1. Infrared spectroscopy and 13C and 29Si nuclear magnetic resonance data are in agreement with the proposed structure. This material has been used to catalyse the addition of nitromethane to cyclopentenone. The catalytic efficiency was followed and the nitromethylcyclopentanone conversion presented a yield of 98% at 3 h of reaction. The catalyst was recovered and reused 14 times, maintaining about 98% of its catalytic efficiency.
publishDate 2006
dc.date.none.fl_str_mv 2006
2017-12-07T04:45:02Z
2017-12-07T04:45:02Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv J. Braz. Chem. Soc.,v.17,n.5,p.994-999,2006
http://repositorio.unb.br/handle/10482/26711
https://dx.doi.org/10.1590/S0103-50532006000500026
identifier_str_mv J. Braz. Chem. Soc.,v.17,n.5,p.994-999,2006
url http://repositorio.unb.br/handle/10482/26711
https://dx.doi.org/10.1590/S0103-50532006000500026
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Sociedade Brasileira de Química
publisher.none.fl_str_mv Sociedade Brasileira de Química
dc.source.none.fl_str_mv reponame:Repositório Institucional da UnB
instname:Universidade de Brasília (UnB)
instacron:UNB
instname_str Universidade de Brasília (UnB)
instacron_str UNB
institution UNB
reponame_str Repositório Institucional da UnB
collection Repositório Institucional da UnB
repository.name.fl_str_mv Repositório Institucional da UnB - Universidade de Brasília (UnB)
repository.mail.fl_str_mv repositorio@unb.br
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