Synthesis and Mesomorphic Properties of N(4-n-alkyloxy salicylidene)4′-n-alkylanilines and their Copper Complexes I

• Published in: Molecular crystals and liquid crystals (Philadelphia, Pa. : 2003) Pa. : 2003), 2002-01, Vol.373 (1), p.105-117
• Main Authors: Rao, Nandiraju V. S., Singha, Dwijamani, Das, Momi, Paul, Manoj Kr
• Format: Article
• Language: English
• ISSN: 1542-1406; 1563-5287
• DOI: 10.1080/713738211

A series of metal (Cu) complexes with bidentate Schiff-bases, i.e., N(4-n-alkyloxy salicylidene)4′-n-alkylanilines obtained by the 1:1 condensation of 4-n-alkyloxy salicylaldehyde and 4-n-alkylanilines, i.e., 4-n-hexylaniline, 4-n-heptylaniline, and 4-n-octylaniline, have been prepared and characterized. The synthesis of the ligands N(4-n-butyloxysalicylidene)-4′-n-alkylanilines as well as the complexes and characterization by thermal microscopy for mesomorphism are presented. The ligands are found to exhibit interesting smetic phases (mostly tilted phases) and polymorphism, while the complexes showed orthogonal smectic A, smectic B, and smectic E phases. The mesomorphic range as well as the polymorphism decreases with increase in chain length. However, the coordination with copper leads to thermally stable metallomesogens possessing larger mesomorphic range but with a reduced number of mesomorphic phases.