Ionic columnarmetallomesogens formed by three-coordianted copper(I) complexes

摘要

Two series of copper(I) complexes (1, 2) derived from bis {2-[3'-(3'',4''-dialkoxyphenyl)-5'-methyl-1'-pyrazolyl]ethyl} ethers and from bis {2-[3'-(3'',4'',5'-trialkoxyphenyl)-5'-methyl-1'-pyrazolyl]ethyl} ethers were prepared and characterized. These ionic copper(I) complexes were obtained by reaction of the ethers with [Cu(MeCN)_4]BF_4 in refluxing acetonitrile. All three-coordinated copper(I) complexes isolated as off-white solids were characterized by NMR spectroscopy and elemental analysis, and their mesomorphic properties were also studied by polarized optical microscopy, differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). Results indicated that these complexes exhibited hexagonal columnar phases (Col_h). The clearing points of all compounds were relatively low (94-112 deg C) and the temperature range of the mesophases was ca. 45-68 deg C. Powder XRD diffraction patterns showed three sharp relfections in the small angle region corresponding to a ratio of their positions of 1: (1/3)~(1/2):(1/2), indicating typical hexagonal columnar phases.