A Cuboidal Cu4S4 Cluster Supported by Bulky Iminothiolate Ligands: Synthesis, Solid-State Structure, and Solution Study

A new tetracopper(I) complex containing a cuboidal Cu4S4 core, [Cu4(dap)4], where dap− is dibenzodiazepinethiolate(1–), has been synthesized and structurally characterized by single-crystal X-ray diffraction analysis. The monoanionic iminothiolate ligand dap− renders the cluster framework exceptionally stable to retain the tetranuclear structure in solution, which allows us to examine for the first time the solution properties of this class of clusters, including UV-vis and NMR spectroscopy and cyclic voltammetry.