Novel Metal−Organic Frameworks Derived from Group II Metal Cations and Aryldicarboxylate Anionic Ligands

Abstract

Reaction of magnesium, calcium, strontium, and barium salts with a range of dicarboxylic acids [benzene-1,4-dicarboxylic acid (H2BDC), naphthalene-2,6-dicarboxylic acid (H2NDC), 4,5,9,10-tetrahydropyrene-2,7-dicarboxylic acid (H2TPDC), pyrene-2,7-dicarboxylic acid (H2PDC), 5,10-dihydroanthracene-2,7-dicarboxylic acid (H2DADC)] in N,N′-dimethylformamide (DMF) or N,N′-diethylformamide (DEF) in Teflon-lined stainless steel autoclaves produces a range of metal−organic framework materials. Single crystal X-ray analysis has confirmed that the predominant building block in these materials is a chain of metal centers bridged either by carboxylate moieties alone as in [M(DMF)(μ-BDC)]∞ (M = Mg or Sr), [Ca1.5(DEF)(μ-BDC)1.5]∞, and [Sr(DEF)(OH2)(μ-BDC)]∞ or bridged by both carboxylate ligands and DMF/DEF molecules as in [M(μ-DMF)(μ-NDC)]∞ (M = Ca, Sr, or Ba), [M(μ-DEF)(μ-TPDC)]∞ (M = Ca or Sr), [M(μ-DMF)(μ-DADC)]∞ (M = Ca or Sr), and [Sr(μ-DEF)(μ-PDC)]∞. In contrast, the isomorphous complexes [Mg3(DMF)4(μ-NDC)3]∞ and...