3-Arylisoxazolyl-5-Carboxylic Acid and 5-(Hydroxymethyl)-3-Aryl-2-Isoxazoline as Molecular Platforms for Liquid-Crystalline Materials
نویسندگان
چکیده
A síntese de uma plataforma molecular para materiais líquido-cristalinos derivados do ácido 3-arilisoxazolil-5-carboxílico (1) e do 5-(hidroximetil)-3-aril-2-isoxazolina (2) é descrita. Os intermediários 1 e 2 são obtidos através da reação de cicloadição [3+2] 1,3-dipolar entre arilóxidos de nitrilas e os dipolarófilos ácido acrílico e álcool alílico, respectivamente. Os compostos cristais líquidos são sintetizados através de uma estratégia de alongamento molecular do núcleo primitivo isoxazolínico pela conexão de subunidades arilacetilênicas, as quais foram obtidas da reação de Sonogashira. Sob essas condições, séries de cristais líquidos 5a-c, 6, 7a-g e 8a-d têm sido sintetizadas com rendimentos de médios para bons. Os compostos finais apresentam propriedades líquido-cristalinas nematogênica e esmectogênica. Um cálculo DFT no nível B3LYP/6-31G(d,p) é também apresentado e alguns parâmetros estruturais obtidos são analisados.
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