Syntheses And Luminescent Properties Of Metal-Organic Frameworks Assembled With A Resorcin[4]Arene-Functionalized Tetracarboxylate

A new family of resorcin[4]arene-based metal-organic frameworks (MOFs), namely, [Eu(HL)(DMF)(H2O)2]·3H2O (1), [Tb(HL)(DMF)(H2O)2]·3H2O (2), [Cd4(L)2(DMF)4(H2O)2]·3H2O (3) and [Zn3(HL)2(H2O)2]·2DMF·7H2O (4), have been constructed from a resorcin[4]arene-functionalized tetracarboxylic acid (H4L= 2,8,14,20-tetra-ethyl-6,12,18,24-tetra-methoxy-4,10,16,22-tetra-carboxy-methoxy-calix[4]are ne). Isostructural 1 and 2 exhibit charming 1D motifs built with the cup-like HL3- anions and rare earth cations.3 and 4 show a unique sandwich-based 2D layer and a fascinating 3D framework, respectively. Remarkably,1 and 2 display intensive red and green emissions triggered by the efficient antenna effect of organic ligands under UV light. More importantly, systematic luminescence studies demonstrate that Ln-MOFs 1 and 2, as efficient multifunctional fluorescent materials, show highly selective and sensitive sensing of Fe3+, polyoxometalates (POMs) and acetone, which represents a rare example of a sensor for quantitatively detecting three different types of analytes. This is also an exceedingly rare example of Fe3+ and POMs detection in aqueous solutions employing resorcin[4]arene-based luminescent Ln-MOFs.