• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Síntese de trifluormetil-cicloalca[d]-2(1h)-pirimidinonas e tiopirimidinonas / Synthesis of trifluoromethyl-cycloalca[d]-2(1h)- pyrimidinones and thiopyrimidinones

Costa, Michelle Budke 20 July 2004 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work describes the synthesis and identification of a serie of 4-trifluoromethylcycloalca[d]-2-(1H)-(thio)pyrimidinones, from the cyclocondensation reactions of 2-trifluoroacetylmethoxycycloalkenes with urea and thiurea. The 2-trifluoroacetylmethoxycycloalkenes were obtained from trifluoroacetylation of acetals derived from cycloalkanones. From this procedure, eight 2-trifluoroacetylmethoxycycloalkenes were obtained in good yields (60-70%), being that five are unpublished in literature. The cyclocondensation reaction using 2-trifluoroacetylmethoxycycloalkenes and urea or thiurea an carried out in alcoholic half under reflux, for 20 hours, catalysed by BF3.OEt2, leading to the products in 10-65% yields. The structural analyses of 2-trifluoroacetylmethoxycycloalkenes and 4- trifluoromethyl-cycloalca[d]-2-(1H)-(thio)pyrimidinones obtained were characterized by NMR 1H, 13C, CG/MS and elemental analysis. Still, were preliminary studies of NMR 17O for the 2-trifluoroacetylmethoxycycloalkenes. / Este trabalho descreve a síntese e caracterização de uma série de 4-trifluormetil-cicloalca[d]-2(1H)-(tio)pirimidinonas, a partir de reações de ciclocondensação de 2-trifluoracetilmetoxicicloalquenos com uréia e tiouréia. Os 2-trifluoracetilmetoxicicloalquenos foram obtidos a partir de reações de trifluoracetilação de acetais derivados de cicloalcanonas. Dentro deste procedimento oito 2-trifluoracetilmetoxicicloalquenos foram sintetizadas em bons rendimentos (60-70%), sendo que cinco são inéditas na literatura. As reações de ciclocondensação empregam 2- trifluoracetilmetoxicicloalquenos e uréia ou tiouréia e foram conduzidas sob refluxo em meio alcóolico por 20 horas, catalisado por BF3.OEt2, levando a rendimentos entre 10-65%. A análise estrutural de 2-trifluoracetilmetoxicicloalquenos, bem como de 4- trifluormetil-cicloalca[d]-2(1H)-(tio)pirimidinonas sintetizados foram caracterizados por RMN de 1H, 13C, CGMS e análise elementar. Além disso foi feito estudos preliminares de 17O para os 2-trifluoracetilmetoxicicloalquenos.
2

Síntese de 2-trialoacetil-1-metoxicicloalquenos e sua aplicação na obtenção de cicloalcapirazóis e isoxazóis derivados / Synthesis of 2-trihaloacetyl-1-metoxycycloalkenes and its application in obtaining cycloalca-pirazoles and isoxazoles derivaties

Costa, Michelle Budke 06 August 2008 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work describes the synthesis and characterization of 2-trihaloacetylmetoxycycloalkenes series derived from cyclical ketones (cyclohexanone, cycloheptanone, cyclooctanone and cyclododecanone). The 2-trihaloacetyl-1-metoxycycloalkenes were obtained from the reaction of trihaloacetylation of 1.1-dimetoxycycloalkanes. Eight 2-trihaloacetyl-1-metoxycycloalkenes have been synthesized, and four of these trichloroacetyl compounds are unprecedented in the literature. The 2-trifluoroacetyl-1-metoxycycloalkenes were employed in the regiospecific synthesis of 3-hydroxy-3-trifluoromethyl-cycloalka[c]isoxazole, 3-trifluoromethyl-cycloalka[c]isoxazole, 3-trifluoromethyl-cycloalka[c]1H-pyrazole, 2-acetyl-3-hydroxy-3-trifluoromethyl-cycloalka[c]1H-pyrazole, 2-carboxyamide-3-hydroxy-3-trifluoromethyl-cycloalka[c]1H-pyrazole, 4-(3-hydroxy-3-trifluoromethyl-cycloalka[c] pyrazole-2-yl]-7-chloroquinoline. The reactions of cyclocondensation employed 2-trifluoroacetyl-1- metoxycycloalkenes and five different 1,2-dinucleofiles (hydroxylamine, hydrazine hydrochloride, acetic hydrazine, semicarbazide and 4-hydrazine-7-chloroquinoline), leading to yield between 34-85%. All compounds were characterized by spectral and analytical experiments, 1H's and 13C's NMR, and its purity was demostrated by CG/MS and elemental analyses. / Este trabalho descreve a síntese e caracterização de uma série de 2-trialoacetil-1-metoxicicloalquenos derivados de cetonas cíclicas (ciclopentanona, cicloexanona, cicloeptanona, ciclooctanona e ciclododecanona). Os 2-trialoacetil-1-metoxicicloalquenos foram sintetizados a partir da reação de trialoacetilação de 1,1-dimetoxicicloalcanos. Foram sintetizadas oito 2-trialoacetil-1-metoxicicloalquenos, sendo que quatro destes compostos tricloroacetilados são inéditos na literatura. Os 2-trifluoracetil-1-metoxicicloalquenos foram empregados na síntese regioespecífica de 3-hidróxi-3-trifluormetil-cicloalca[c]isoxazol, 3-trifluormetilcicloalca[ c]isoxazol, 3-trifluormetil-cicloalca[c]1H-pirazol, 2-acetil-3-hidróxi-3-trifluormetil-cicloalca[c]1H-pirazol, 2-carboxiamida-3-hidróxi-3-trifluormetilcicloalca[c]1H-pirazol, 4-{3-hidróxi-3-trifluormetil-cicloalca[c]pirazol-2-il]-7-cloroquinolina. As reações de ciclocondensação empregaram 2-trifluoracetil-1- metoxicicloalquenos e cinco diferentes 1,2-dinucleófilos, hidroxilamina, cloridrato de hidrazina, hidrazina acética, semicarbazida e 4-hidrazina-7-cloroquinolina, levando a rendimentos entre 34-85%. A análise estrutural de 2-trialoacetil-1-metoxicicloalquenos, bem como os cicloalca[c]azo compostos sintetizados foram caracterizados por experimentos de RMN de 1H, 13C, e sua pureza determinada via CGMS e análise elementar.

Page generated in 0.0418 seconds