Synthesis and mesogenic properties of some beta-diketones and their copper (II) and palladium (II) chelates

Abstract

The paper deals with the synthesis and mesomorphic properties of some new copper (II) and palladium (II) complexes. Some of the ligands which are used to form these complexes also exhibit mesophases. The different mesophase types have been characterised. While none of the ligands shows a nematic phase, some of the copper and palladium chelates do exhibit a metastable nematic phase. A homologous series of eight bis[1-(p-n-alkylbiphenyl)3-(phenyl) propane 1,3-dionato copper (II) has been prepared and all the homologues show a metastable nematic phase. A plot of the nematic rarr isotropic transition temperatures versus the number of carbon atoms in the alkyl chain shows smooth curve relationship.