Discotic Liquid Crystals of Transition Metal Complexes 7¹ : Dimer Discotic Rectangular Ordered Mesophase in Bis(p-n- alkoxybiphenylbutane-1,3-dionato)copper (II) Complexes

Abstract

A novel series of bis(p-n-alkoxybiphenylbutane-1,3-dionato)copper(II) complexes (n-alkoxy = C_nH_2n+1, O, n = 8 ∼ 12, 16, 18) have been synthesized and characterized. The C_nO-Cu complexes for n = 9 ∼ 12, 16, and 18 have a unique dimer discotic rectangular ordered columnar (D₁₀ mesophase. The X-ray diffraction powder pattern of the D₁₀ mesophase of the C₁₆O-Cu complex at 185[ddot]C gave the intradimer distance 5.12 Å, the interdimer distance in the column 9.40 A, and the two-dimensional rectangular lattice constants a = 46.8 Å, b = 16.7 Å. The type of the present D₁₀, mesophase could be assigned as D₁₀ (C2/m).

Key Words:

• discotic liquid crystal
• metal complex
• dimer
• β-diketonato copper(II)