Liquid-crystalline behaviour of di- and mono-palladium organyls: two ways of lyomesophase formation

Abstract

Three members of a series of lath-like dinuclear complexes [Pd₂(µ-Cl)₂(C,N)₂ ] 1, (C,N=orthopalladated imine R¹ –C₆H₃ –CH=N–C₆H₄ –R² ; R¹=alkoxy chain; R²=alkyl or alkoxy chain), a dinuclear cyclopalladated complex with mixed bridges (acetate/thiolate) 2 and a mononuclear orthopalladated complex incorporating a β-diketonate ligand 3, have been synthesized and their lyotropic phase behaviour in mixtures with apolar organic solvents (linear alkanes, cycloocta-1,5-diene or limonene) has been studied. The lyotropic mesomorphism is determined by the combination of the length of the metalloorganyl side chains and the length of alkane used as solvent. Two ways of formation of lyotropic phases are found. The first case of lyotropic chiral nematic (cholesteric, N*) phase formation in a binary system composed of a non-chiral di- or mono-palladium organyl and a chiral apolar organic solvent is reported.

References

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