New [2 × 2] cyclic framework that induces distortions from square planar to tetrahedral around the copper(II) centers

A new tetracopper(II) complex [Cu4(bsbd)4] (bsbd = bis(N-salicylidene)benzene-1,4-diamine) has been prepared and structurally characterized. The complex constructs a [2 × 2] cyclic coordination framework, which inhibits formation of square planar copper(II) centers, and induces distortion to a tetrahedral structure. The effects of the distortions on the absorption spectra are characterized.

Graphical abstractA new [2 × 2] metallacyclic framework was constructed by combination of four copper(II) ions and four bis-didentate bridging ligands, bis(N-salicylidene)benzene-1,4-diamine (bsbd). The complex, [Cu4(bsbd)4], gives tetrahedrally distorted copper(II) centers, and a resulting rhombus cyclic framework.Figure optionsDownload full-size imageDownload as PowerPoint slide