Metallomesogens Derived from Pyrazoles and α-[2-[(2-Hydroxyphenyl)imino]ethylidene]-benzenemethanols

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In this thesis three series of new compounds were prepared and their mesomorphic properties investigated. All organic derivatives were characterized by 1H-NMR and 13C-NMR spectroscopes, whereas all metal complexes were characterized by IR spectroscopy and elemental analysis. Their physical properties were characterized by polarized optical microscopy (POM), differential scanning calorimetry (DSC), and temperature-dependent powder X-ray diffraction (XRD) measurements. In Series I, preparation, characterization and mesomorphric properties of copper(II) complexes derived from 3-[(4-alkoxy)phenyl]-1H-pyrazoles (Rpc) were described. X-ray single crystal structural analysis showed that these complexes were square-planar coordinated. The formation of mesophases was found to be sensitive to the number of carbon length of the side chains. All derivatives with shorter alkoxy chains (n = 8) exhibited nematic phase, however, all other derivatives with longer alkoxy chains (n = 10, 12, 14, 16) formed smectic C phases. In Series II, bis[?[2-[3,4-alkoxy-2-hydroxphenyl]imino]ethylidene]- 4-alkoxybenzenemethanols (2Rrs) and their metal complexes (M = Cu, Zn, Pd) were synthesized, and their mesomorphic properties studied. All derivatives 2Rrs exhibited smectic C phases. All copper(II) complexes (2Rrc; n = 8, 10, 12, 14,16 ) and zinc(II) complexes (2Rrz; n = 16) exhibited columnar hexagonal phases (Colh) phases. On the other hand, palladium complexes (2Rrp; n = 16) formed an unknown mesophases. In Series III, bis[?[2-[4-alkoxy-2-hydroxphenyl]imino]ethylidene]- 4-alkoxybenzenemethanols (Rrs; n = 8, 12, 16) and their metal complexes (M = Cu, Pd, Zn) were prepared and their mesomorphic properties investigated. All ligand derivatives exhibited smectic X and smectic C phase. Zinc(II) complexes (Rrz; n = 8, 12, 16) exhitbited smectic A or smectic C phases. However, palladium complexes (Rrp; n = 16) formed smectic X phases. Copper complexes (Rrc; n = 16) was not mesogenic.