Facile Synthesis of a Series of 2-(4-Alkyloxyphenyl)-5-cyanopyridine Liquid Crystalline Compounds
作者:Win-Long Chia、Yu Wei Cheng
DOI:10.3987/com-07-11224
日期:——
This study describes the facile synthesis of a homologous series of pyridine-containing liquid crystalline 2-(4-alkyloxyphenyl)-5-cyanopyridines (nOPPyCN, n = 3-7). The subject liquid crystals were prepared in a short two-step reaction. First, 4-alkyloxyphenylmagnesium bromides were added to N-phenyloxycarbonyl-3-cyanopyridinium chloride, affording a 1,2-dihydropyridine, which was then oxidized by o-chloronil. The resulting products, 2-(4-alkyloxyphenyl)-5-cyanopyridines, were obtained in good yields (72%-83%). Thermotropic behaviors of these liquid crystals were investigated using differential scanning calorimetry (dsc) and polarized optical microscopy (pom).