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Lanthanide complexes of a steroid-substituted benzocrown ether were synthesised. The metal-to-ligand ratio of all the metal complexes is 1∶1. The ligand 4′-[(cholesteryloxy)carbonyl]-benzo-15-crown-5 is a monotropic liquid crystal, displaying a cholesteric mesophase. The lanthanide complexes with nitrate counter-ions form a highly viscous mesophase, decomposing at the clearing point. The transition temperatures change as a function of the lanthanide ion. The corresponding lanthanide complexes with dodecylsulphate (DOS) counter-ions do not form a mesophase. In both cases, the metal complexes have a much lower melting point than the parent ligand.
Lanthanide complexes of a steroid-substituted benzocrown ether were synthesized. The metal-to-ligand ratio of all the metal complexes is 1: 1. The ligand 4 ’- [(cholesteryloxy) carbonyl] -benzo- 15-crown-5 is a monotropic liquid crystal, displaying a cholesteric mesophase. The lanthanide complexes with nitrate counter-ions form a highly viscous mesophase, decomposing at the clearing point. The transition temperatures change as a function of the lanthanide ion. The corresponding lanthanide complexes with dodecylsulphate (DOS) counter-ions do not form a mesophase. In both cases, the metal complexes have a much lower melting point than the parent ligand.