Structural Variation and Luminescence Properties of Tri- and Dinuclear CuII and ZnII Complexes Constructed from a Naphthalenediol-Based Bis(Salamo)-type Ligand

Three trinuclear complexes constructed from a naphthalenediol-based bis(Salamo)-type tetraoxime ligand (H4L1), [Cu-3(L-1)(OAc)(2)]center dot CH3OH (1), [Zn-3(L-1)(OAc)(2)(CH3OH)(2)]center dot 4CHCl(3) (2), and [Cu-2(L-1)Na(NO3)(CH3OH)] (3), and one dinuclear complex, [{Cu(L-2)}(2)] (4), based on an unexpected ligand H2L2 derived from the cleavage of H4L1 have been synthesized and characterized by X-ray diffraction analyses. Different anionic sources, transition metal salts, and rationally controlled reaction conditions play important roles in the construction of the resulting complexes with variable coordination geometries (coordination number ranges from 4 to 7), and four types of supramolecular network were controlled by noncovalent interactions, such as hydrogen bond, p center dot center dot center dot p stacking, CH center dot center dot center dot p, Cu center dot center dot center dot p, and halogen-related interactions. The fluorescence properties of H4L1 and its complexes were investigated, and 2 exhibits unique bright cyanyellow visible fluorescent emissions in different solvents.