Ln-MOF Pseudo-Merohedral Twinned Crystalline Family as Solvent-Free Heterogeneous Catalysts

Hydrothermally promoted assembly of the multifunctional 3,5-disulfobenzoic acid (3,5-DSB) ligand with the lanthanide series and the 1,10-phenanthroline as a secondary ligand gives rise to the formation of 2D coordination polymers. The isostructural <b>RPF-20-Ln</b> series, with formula <b>[Ln­(3,5-DSB)­(Phen)­(H<sub>2</sub>O)]·H<sub>2</sub>O</b> (<b>Ln</b> = <b>Sm</b>,<b> Eu</b>,<b> Gd</b>,<b> Tb</b>,<b> Dy</b>,<b> Ho</b>,<b> Er</b>, and <b>Yb</b>), present pseudomerohedral twinned crystals. The polymeric network consists of uninodal 2D net (4<sup>3</sup>·6<sup>3</sup>) layers perpendicular to the [010] direction. π–π Stacking interactions between them gives rise to the tridimensional supramolecular framework. The new compounds were tested as catalysts in acid Lewis reactions. A comparative study with other lanthanide MOFs inside the systems Ln/DSB and Ln/DSB/Phen reveals some structural facts that could improve the catalytic behavior of this kind of material.