Pyrazole synthesis under microwave irradiation and solvent-free conditions
Autor(a) principal: | |
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Data de Publicação: | 2010 |
Outros Autores: | , , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Journal of the Brazilian Chemical Society (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010000600012 |
Resumo: | This paper presents a study of solvent-free reaction conditions using microwave irradiation (MW) to obtain 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles by the cyclocondensation reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3C(O)CH=C(R¹)OR, where R/R¹ = Et/H, Me/Me and Me/Ph] with hydrazines [NH2NH-R², where R² = CO2Me, Ph, CH2CH2OH]. Some reactions were performed under the same reaction conditions using methanol as solvent. The results obtained using MW equipment for synthesis under solvent-free conditions were also compared with those described in literature for conventional thermal heating and heating with a domestic MW oven. In general, the products furnished by reaction in MW equipment for synthesis presented better yields and shorter reaction times. In addition, it was demonstrated that the reaction temperature altered the formation of products for each hydrazine showing that MW equipment for synthesis is efficient for reacting hydrazines and 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones to procedure the products 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles. |
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Pyrazole synthesis under microwave irradiation and solvent-free conditionsmicrowave irradiationsolvent-freepyrazolescyclocondensation reactionsThis paper presents a study of solvent-free reaction conditions using microwave irradiation (MW) to obtain 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles by the cyclocondensation reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3C(O)CH=C(R¹)OR, where R/R¹ = Et/H, Me/Me and Me/Ph] with hydrazines [NH2NH-R², where R² = CO2Me, Ph, CH2CH2OH]. Some reactions were performed under the same reaction conditions using methanol as solvent. The results obtained using MW equipment for synthesis under solvent-free conditions were also compared with those described in literature for conventional thermal heating and heating with a domestic MW oven. In general, the products furnished by reaction in MW equipment for synthesis presented better yields and shorter reaction times. In addition, it was demonstrated that the reaction temperature altered the formation of products for each hydrazine showing that MW equipment for synthesis is efficient for reacting hydrazines and 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones to procedure the products 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles.Sociedade Brasileira de Química2010-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010000600012Journal of the Brazilian Chemical Society v.21 n.6 2010reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50532010000600012info:eu-repo/semantics/openAccessBuriol,LilianFrizzo,Clarissa P.Marzari,Mara R. B.Moreira,Dayse N.Prola,Liziê D. T.Zanatta,NiloBonacorso,Helio G.Martins,Marcos A. P.eng2010-07-19T00:00:00Zoai:scielo:S0103-50532010000600012Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2010-07-19T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
title |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
spellingShingle |
Pyrazole synthesis under microwave irradiation and solvent-free conditions Buriol,Lilian microwave irradiation solvent-free pyrazoles cyclocondensation reactions |
title_short |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
title_full |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
title_fullStr |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
title_full_unstemmed |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
title_sort |
Pyrazole synthesis under microwave irradiation and solvent-free conditions |
author |
Buriol,Lilian |
author_facet |
Buriol,Lilian Frizzo,Clarissa P. Marzari,Mara R. B. Moreira,Dayse N. Prola,Liziê D. T. Zanatta,Nilo Bonacorso,Helio G. Martins,Marcos A. P. |
author_role |
author |
author2 |
Frizzo,Clarissa P. Marzari,Mara R. B. Moreira,Dayse N. Prola,Liziê D. T. Zanatta,Nilo Bonacorso,Helio G. Martins,Marcos A. P. |
author2_role |
author author author author author author author |
dc.contributor.author.fl_str_mv |
Buriol,Lilian Frizzo,Clarissa P. Marzari,Mara R. B. Moreira,Dayse N. Prola,Liziê D. T. Zanatta,Nilo Bonacorso,Helio G. Martins,Marcos A. P. |
dc.subject.por.fl_str_mv |
microwave irradiation solvent-free pyrazoles cyclocondensation reactions |
topic |
microwave irradiation solvent-free pyrazoles cyclocondensation reactions |
description |
This paper presents a study of solvent-free reaction conditions using microwave irradiation (MW) to obtain 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles by the cyclocondensation reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3C(O)CH=C(R¹)OR, where R/R¹ = Et/H, Me/Me and Me/Ph] with hydrazines [NH2NH-R², where R² = CO2Me, Ph, CH2CH2OH]. Some reactions were performed under the same reaction conditions using methanol as solvent. The results obtained using MW equipment for synthesis under solvent-free conditions were also compared with those described in literature for conventional thermal heating and heating with a domestic MW oven. In general, the products furnished by reaction in MW equipment for synthesis presented better yields and shorter reaction times. In addition, it was demonstrated that the reaction temperature altered the formation of products for each hydrazine showing that MW equipment for synthesis is efficient for reacting hydrazines and 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones to procedure the products 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles. |
publishDate |
2010 |
dc.date.none.fl_str_mv |
2010-01-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010000600012 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010000600012 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-50532010000600012 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
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 |
Journal of the Brazilian Chemical Society v.21 n.6 2010 reponame:Journal of the Brazilian Chemical Society (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Journal of the Brazilian Chemical Society (Online) |
collection |
Journal of the Brazilian Chemical Society (Online) |
repository.name.fl_str_mv |
Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
||office@jbcs.sbq.org.br |
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1750318171033698304 |