Through different synthetic strategies, four dinuclear cadmium(II) complexes containing N2O/N2O2 donor tridentate/tetradentate asymmetrical Schiff base ligands have been synthesized and characterized. The two complexes [Cd(L1)(μ2-Cl)(CH3OH)]2 (1) and [Cd(L2)Cl]2·CH3OH (2) are constructed, respectively, from self-assembly of a Cd2+ ion with two asymmetrical Schiff base ligands, namely 2-((2-(dimethylamino)ethylimino)methyl)phenol (HL1) and 2-((2-(dimethylamino)ethylimino)methyl)-6-methoxyphenol (HL2). However, via single-crystal to single-crystal structural transformations driven by temperature, the other two corresponding compounds [Cd(L1)Cl]2 (1a) (1 → 1a) and [Cd(L2)Cl]2 (2a) (2 → 2a), with N2O2Cl and N2O3Cl donors, respectively, can be obtained. Obviously, the synthetic strategies presented in the text provide very effective methods for constructing the dinuclear CdII compounds with N2O/N2O2 donor tridentate/tetradentate asymmetrical Schiff base ligands. Meanwhile, the strong fluorescence emission of 1 and 2 makes them potentially useful photoactive materials.
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