A systematic study has been made of the liquid crystalline properties of two types of copper complexes derived from enamino-beta-ketonate and iminopropyl-beta-ketonate Schiff bases that exhibit mesomorphism. These complexes are structurally similar, and all have a bimetallic center as an expanded core group. The mesophase stability depends upon the steric bulk between the layer structures. The enamino-beta-ketonate complexes exhibit smectic A phases, however, the iminopropyl-beta-diketonates are not liquid crystalline. Examination of the structural features of these complexes revealed that the presence of a methyl group attached to the core group was the cause for the lack of liquid crystallinity observed in the latter. The crystal and molecular structure of bis[3,5-dioctanoylphenyl 2-(3-hydroxypropyl)iminopropyl ketonato]copper(II) was determined by means of X-ray analysis. The Cu Cu intramolecular separation is 3.0375(5) Angstrom. The planar geometry is slightly distorted toward square pyramidal by displacement of the copper by 0.018 Angstrom from the mean plane through atoms N(1), O(2), O(1A) and O(1).
關聯:
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
