• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1350-1360
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• 2001

The synthesis and characterization of very stable Pd(Ⅱ) η1-imine complexes of bis(3,4-dialkyloxybenzylidene-3', 4'-dialkyloxyaniline)dichloropalladium(Ⅱ) with alkyl chain of hexyl (8), octyl (9), decyl (10) and dodecyl (11) groups, a nd of bis(4-ethyloxybenzylidene-4'-ethyloxyaniline)dichloropalladium(Ⅱ) as a model complex are described. The molecular structure with twisted board-like geometry of the complex resulting from the coordination of Pd(Ⅱ) with η1-imine bonding was confirmed by X-ray crystallographic analysis of the model complex. In contrast to the imine ligands, all the complexes with an exception of 11 display a thermally stable monotropic smectic A mesophase without any decomposition of the complex. These results, characterized by a combination of differential scanning calorimetry, optical polarized microscopy, and powder X-ray scattering experiments, are discussed.