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dc.contributor.authorFritsch, Lumapt_BR
dc.contributor.authorMerlo, Aloir Antoniopt_BR
dc.date.accessioned2016-09-16T02:13:55Zpt_BR
dc.date.issued2016pt_BR
dc.identifier.issn2365-6549pt_BR
dc.identifier.urihttp://hdl.handle.net/10183/148207pt_BR
dc.description.abstractSchiff bases are in action again showing an exuberant mesophase range despite their chemical and thermal weakness. Two series of Schiff bases (SB), based on isoxazolines 9 a–f and isoxazoles 10 a–f, are described. 9 a–f were synthesized by a [3+2] cycloaddition 1,3-dipolar of arylnitrile oxide from p-nitrobenzaldehyde (1) and alkenes. And, subsequently oxidized to 10 a–f by MnO2. The isoxazolines and isoxazoles thus obtained were reduced to aniline derivatives and condensed with appropriated arylaldehydes. The SBs series isoxazolines 9 a–f presented a narrow mesophase range, while SBs series isoxazoles 10 a–f showed a large mesophase range. Nematic mesophase was observed for SBs with short and non-polar groups, while SmA and SmC mesophase for SBs with long and more polar terminal groups. The stability of the SBs is also dependent on the clearing temperature. For 10 a–f with high clearing temperature, decomposition induced by heat was observed during the first cycle of heating and in solutions of CDCl3. Series 9 a–f was more resistant to the thermal decomposition.en
dc.format.mimetypeapplication/pdf
dc.language.isoengpt_BR
dc.relation.ispartofChemistrySelect. Weinheim, Alemanha. Vol. 1, no. 1 (Jan. 2016), p. 23-30pt_BR
dc.rightsOpen Accessen
dc.subjectCristais líquidospt_BR
dc.subjectIminaspt_BR
dc.subjectCompostos orgânicos : Síntesept_BR
dc.subjectBase de Schiffpt_BR
dc.subjectIsoxazolinaspt_BR
dc.subjectIsoxazolespt_BR
dc.titleAn old dog with new tricks : schiff bases for liquid crystals materials based on isoxazolines and isoxazolespt_BR
dc.typeArtigo de periódicopt_BR
dc.identifier.nrb001001764pt_BR
dc.type.originEstrangeiropt_BR


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