Metal-organic polyhedron from flexible tetrakis(thiobenzyl-carboxylate)-Tetrathiafulvalene

The synthesis of crystalline self-assembled materials starting from building blocks with a large degree of freedom is challenging. Furthermore, incorporating redox-active moieties in self-assembled metal organic polyhedra is of the outmost interest to modulate the properties of the cavity through redox stimuli. Herein is presented the synthesis of a novel electroactive ligand bearing four coordinating moieties around an S-alkylated tetrathiafulvalene (TTF) scaffold. The redox behavior of the ligand is similar to a tetra-S-alkylated TTF. In the solid state, it presents a densely packed H-bonded 1D polymeric structure. Upon reaction with Cu(OAc)2 in the presence of dimethylformamide or dimethylacetamide, two novel M4L4-type metal-organic polyhedra (MOPs) bearing paddlewheel metal clusters as connecting nodes are obtained. The structural features and electrochemical properties of the ligand and the MOPs are devised. Both MOPs adopt the same structure characterized by a tetrahedral arrangement of the four TTF moieties.