LIQUID-CRYSTALLINE COMPLEXES OF PALLADIUM(II) AND PLATINUM(II) WITH DI-ALKOXYSTILBAZOLES AND TRI-ALKOXYSTILBAZOLES - LIGAND CONTROL OF MESOMORPHISM

Liquid-crystalline complexes of palladium and platinum are formed when the metals are complexed to stilbazoles (4-styrylpyridines) bearing e ither two or three alkoxy chains. The complexes, termed polycatenar, s how smectic C mesophases for most 3,4-disubstituted ligands, while the use of trisubstituted ligands leads to complexes showing columnar org anisation, demonstrating that the spatial organisation of the metals i n the liquid-crystal mesophase can be rather readily controlled. Compl exes of these di-and tri -substituted stilbazoles with a cis-dicarbony lchloroiridium(I) fragment were not liquid crystalline.