Mechanochemical Access to Elusive Metal Diphosphinate Coordination Polymer

Several binary metal diphosphinate compounds (ML) have been reported for diphosphinate bonded by a single methylene fragment. In case of longer bridges, binary products are difficult to isolate in crystalline form. Here, using a solvent assisted mechano-chemistry synthesis, we report two new ML crystalline phases, one hydrated and one anhydrous. The hydrated phase is a 2D coordination polymer with an open framework structure. Its network displays a new topology for coordination polymers and metal organic frameworks. The thermal behavior of the two phases has been studied. Finally, the importance of the bridge length is discussed in view of known metal diphosphinate compounds.