Mesogenic Enaminoketone Ni(II) Complexes of Phenazine and Quinoxaline Derivatives

The new Ni(II) metallomesogenes were synthesized. Their mesogenic cores are constructed from tetradental enaminoketone unit connected to 1,2:3,4-di(4,5-dioctyloxybenzo)phenazine or 2,3-di(3,4-dioctyloxyphenylo)quinoxaline. The described compounds form columnar hexagonal phase (Colhd) in very broad temperature range. The high stability of the columnar phase results from presence of a permanent dipol moment in enaminoketone moieties created by strong electron withdrawing properties of carbonyl groups.