1,2,4,5-Benzene-tetra-carboxylic acid: a versatile ligand for high dimensional lanthanide-based coordination polymers

Abstract

Reactions in water between 1,2,4,5-benzene-tetra-carboxylate and lanthanide ions lead to seven families of lanthanide-containing coordination polymers with respective chemical formulae {[Tm₄(btec)₃(H₂O)₁₀]·7H₂O}_∞ (Family 1), {[Ln₄(btec)₃(H₂O)₁₀]·16H₂O}_∞ with Ln = Ho and Tm (Family 2), {[Ln₄(btec)₃(H₂O)₁₂]·12H₂O}_∞ with Ln = Er, Tm and Y (Family 3), {[Ln₄(btec)₃(H₂O)₁₂]·11H₂O}_∞ with Ln = Er, Tm and Y (Family 4), {[Gd₄(btec)₃(H₂O)₁₄]·14H₂O}_∞ (Family 5), {[Ln₅(btec)₃(Hbtec)(H₂O)₁₂]}_∞ with Ln = Eu and Gd (Family 6) and {[KGd₅(btec)₄(H₂O)₁₃]·11H₂O}_∞ (Family 7). All these compounds have been obtained by slow diffusion through water or gel media. They have been structurally characterized. Six out of the seven families are three-dimensional and their potential porosities have been estimated by a computational method. Compounds that belong to families 2, 4 and 6 present a potential porosities of 1281 m ⁻¹, 1156 m² g⁻¹ and 836 m² g⁻¹, respectively.