Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work describe the regiospecific synthesis of three novel series of 1-(2-thenoyl)-, 1-(2-furoyl)- and 1-(isonicotinoyl)-3-alkyl(aryl)[heteroaryl]-5-hydroxy-5-trihalomethyl-4,5-dihydro-1H-pyrazoles, in good yields (50 91 %), from the cyclocondensation reactions of 1,1,1-trifluoro(chloro)-4-alkoxy-4-alkyl(aryl)[heteroaryl]-3-alken-2-ones, where alkyl = H and Me; aryl = Ph, 4-MePh, 4-OMePh, 4-FPh, 4-ClPh, 4-BrPh, 4-NO2Ph; heteroaryl = 2-thienyl e 2-furyl with 2-thiophenecarboxylichydrazide, furoic hydrazide and isonicotinic acid hydrazide, respectively. Subsequently dehydration reaction of 1-(2-thenoyl)-, 1-(2-furoyl)- pyrazolines trihalomethyl substituted in chloroform / P2O5, depending of the trihalomethyl substituent, furnished the corresponding 1H-pyrazoles trichloromethylated in low yields (21 29 %), or 1Hpyrazoles trifluoromethylated as mixture of regioisomers and in yields (35 36 %). The 1-isonicotinoyl pyrazolines trihalomethyl substituted was extremely resistant to dehydration reactions with chloroform / P2O5 at reflux for 48 hours or with acetic acid at reflux for 4 hours. In both cases, the 2-pyrazolines were recovery without any structural modification. All compounds have been characterized by analytical and spectral data (1H and 13C-NMR, GC-MS, and elemental analyses). / Este trabalho descreve a síntese regioespecífica de três novas séries de 1-(2-tenoil)-, 1-(2-furanoil)- e 1-(isonicotinoil)-3-alquil(aril)[heteroaril]-5-hidroxi-5-trialometil-4,5-diidro-1H-pirazóis, em bons rendimentos (50 91%), a partir da reação de ciclocondensação de 1,1,1-trifluor(cloro)-4-alcoxi-4-alquil(aril)[2-heteroaril]-3-alquen-2-onas, onde alquil = H e Me; aril = Ph, 4-MePh, 4-OMePh, 4-FPh, 4-ClPh, 4-BrPh, 4-NO2Ph; heteroaril = 2-tienil e 2-furil com 2-tenoil-, 2-furanoil- e isonicotinoil-hidrazinas, respectivamente. Subseqüentemente, reações de desidratação de 1-(2-tenoil)-, 1-(2-furanoil)-pirazolinas trialometil substituídas em meio clorofórmio / P2O5, dependendo do substituinte trialometil, forneceram os correspondentes 1H-pirazóis triclorometilados em baixos rendimentos (21 29%), ou 1H-pirazóis trifluormetilados com mistura de regioisômeros e em rendimentos (35 36 %). As 1-isonicotinoil pirazolinas trialometil substituídas foram extremamente resistentes para reações de desidratação com clorofórmio / P2O5 a refluxo por 48 horas ou com ácido acético a refluxo por 4 horas. Em ambos os casos, as 2-pirazolinas foram recuperadas sem modificação estrutural. Todos os compostos foram caracterizados por dados espectrais e analíticos (RMN de 1H, 13C, CGMS e análise elementar).
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufsm.br:1/4149 |
| Date | 20 December 2004 |
| Creators | Oliveira, Marli Redin |
| Contributors | Bonacorso, Helio Gauze, Martins, Marcos Antonio Pinto, Zanatta, Nilo, Siqueira, Geonir Machado, Rubin, Maribel Antonello |
| Publisher | Universidade Federal de Santa Maria, Programa de Pós-Graduação em Química, UFSM, BR, Química |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFSM, instname:Universidade Federal de Santa Maria, instacron:UFSM |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | 100600000000, 400, 300, 300, 300, 300, 300, 300, 06c852ad-d805-43c3-99d6-93a6a86f507c, ae4e4cf9-e020-47ee-874e-84a676dd84fd, a8bc3c8e-4034-458b-a211-6be4a0d7001b, 2f7bd6ce-78fa-4968-ac66-2d1407e90f60, 3b4bc502-9bc1-4539-9874-d13383d8e3dc, 4e00cef5-a143-41b6-823b-85c46190f429 |
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