Robust Metal-Organic Frameworks Based on Tritopic Phosphonoaromatic Ligands

Microporous metal-organic frameworks (MOFs) based on phosphonic ligands are still a very small family of materials if compared to carboxylate-based MOFs, due to some inherent features that make them challenging to synthesize and to characterize. Nonetheless, metal phosphonates display remarkable chemical and thermal robustness that could represent an asset in terms of their employment for practical applications. This feature makes them attractive as alternative materials to classical carboxylate-based MOFs, which often suffer from limited stability. In recent years a number of tritopic phosphonoaromatic ligands have been used as building blocks with the aim of generating open-framework structures. The approach has often proved to be successful and several microporous compounds have been discovered.