Cholesterol-based dimesogenic bidentate ligands and their Cu( II) and Pd( II) metallomesogens

The synthesis and evaluation of the liquid crystalline properties of non-co nventional liquid crystals, consisting of two non-identical mesogenic segme nts interconnected via a paraffinic chain spacer, are of considerable curre nt interest. In particular, chiral dimesogens possessing a cholesteryl este r unit as the chiral entity joined to other aromatic mesogens through a pol ymethylene spacer have shown unique and interesting thermal behaviour. In c ontinuation of our investigations on this topic, here we present the synthe sis and characterization of the first examples of cholesterol-based unsymme trical dimesogenic bidentate ligands and their Cu(II) and Pd(II) metal-orga nic systems (metallomesogens). Our studies reveal that the dimesogenic bide ntate ligands exhibit multiple mesophases, whereas their metal complexes st abilize only the mesophase.