| 摘要: | Two homologous series of 1-(4-alkoxy-2-hydroxyphenyl)-3-(3,4,5-trialkoxyphenyl)propane-1,3-diones and 1-(2-hydroxyphenyl)-3-(3,3, 5-trialkoxyphenyl)propane-1,3-diones were prepared by base-catalysed rearrangement of 4-alkoxy-2-(3,4,5-trialkoxybenzoyloxy)ac and 2-(3,4,5-trialkoxybenzoyloxy)acetophenones respectively. The reaction of these beta,delta-triketones with copper(Ir) acetate gave liquid-crystalline dicopper complexes, bis[1-(4-alkoxy-2-hydroxyphenyl)-3-(3,4, 5-trialkoxyphenyl)propane-1,3-dionato]- and bis[1-(2-hydroxyphenyl)-3-(3,4,5-trialkoxyphenyl) 1,3-dionato]-copper(II). These copper complexes exhibit disordered hexagonal columnar (D-bd,,) mesophases which were identified by DSC analysis and polarized optical microscopy, and were also confirmed by X-ray powder diffraction. The variable-temperature EPR spectra were also studied. |
