matel complexes of schiff - base ligand; Synthesis, characterization and liquid crystalline properties

Abstract

In this work a Schiff base ester derived ligand [H₂L¹]  were synthesized in three steps, first Synthesis of the pentanoiyl chloride from reaction thionyl chloride with pentanoic  acid.

      in the second  step the precursosr (W1), 4-[3-(3-hydroxy-1-methyl- butylideneamino)- 4-methyl-phenylimino]-pentan-2-ol ,was prepared by the reaction of acetylaceton  with tolylen2,4-diamin . In the theird step the ligands were synthesized by the reaction of precursor (W1)with pentanoiyl chloride to produce[H₂L¹] 1:2 mole ratio. The binuclear complexes with Cr³⁺, Co²⁺ and Zn²⁺, were synthesized by the reaction of the ligand with metal salts in 1:1 mole ratio. The compounds were characterized by spectroscopic methods [FT-IR, UV-Vis, CHN, ¹H-NMR] elemental analysis, along with conductivity, and melting point measurements. The structure of the complexes were obtained according to the previous studies. Finally the liquid crystalline properties of the prepared compounds were studied by hot stag  and DCS.