Synthesis and crystal structure of a new coordination polymer based on lanthanum and 1,4-phenyl-enedi-acetate ligands.

Magatte Camara,Mamoudou Diallo,Carole Daiguebonne,Insa Badiane,Olivier Guillou

doi:10.1107/s2056989019002378

Abstract

Reaction in gel between the sodium salt of 1,4-phenyl-enedi-acetic acid (Na2C10O4H8-Na2 p-pda) and lanthanum chloride yields single crystals of the three-dimensional coordination polymer poly[[tetra-aqua-tris-(μ-1,4-phenyl-enedi-acetato)-dilanthanum(III)] octa-hydrate], {[La2(C10H8O4)3(H2O)4]·8H2O}∞. The LaIII coordination polyhedron can be described as a slightly distorted monocapped square anti-prism. One of the two p-pda2- ligands is bound to four LaIII ions and the other to two LaIII ions. Each LaIII atom is coordinated by five ligands, thereby generating a metal-organic framework with potential porosity properties.

Highlights

Most of the organic ligands used in metal–organic frameworks (MOFs) chemistry are rigid aromatic carboxylates (Luo et al, 2007; Huang et al, 2009)
In this paper we report the synthesis and the crystal structure of a new coordination polymer with chemical formula [La2(p-pda)3(H2O)4Á8H2O]1
Other crystal structures of lanthanide coordination polymers with the p-pda2À ligand have been reported previously. This series of compounds, first described by Pan et al (2003) has been widely studied because of potential applications in various fields such as explosives detection (Singha et al, 2014, 2015), gas sorption (Pan et al, 2003) or catalysis (Ren et al, 2011). These compounds, with general chemical formula [Ln2(p-pda)3(H2O)Á2H2O]1 with Ln = La–Ho have been obtained by hydrothermal synthesis and present a lower hydration rate and a higher density than [La2(p-pda)3(H2O)4Á8H2O]1 {Dcalc = 1871 g cmÀ3 for [Ln2(p-pda)3(H2O)Á2H2O]1}

Summary

Chemical context

One of the most important fields of research in coordination chemistry and crystal engineering has been the design of metal–organic frameworks (MOFs), because of their intriguing network topologies and possible applications in gas storage (Eddaoudi et al, 2002; Reneike et al, 1999; Luo et al, 2011a,b; Kustaryono et al, 2010), catalysis (Lee et al, 2009), separation (Hamon et al, 2009), luminescence (Cui et al, 2012; Daiguebonne et al, 2008; Binnemans, 2009;) and molecular magnetism (Calvez et al, 2008; Sessoli et al, 2009). For the synthesis of MOFs, usually two complementary molecular precursors, a cation with vacant coordination sites and a bridging anion, are used to form the coordination polymer. This procedure offers the prospect of rationally designing extended solids with interesting properties. In this paper we report the synthesis and the crystal structure of a new coordination polymer with chemical formula [La2(p-pda)3(H2O)4Á8H2O]1

Structural commentary

Synthesis and crystallization

Refinement

H2A H2B OW1 HW1A HW1B OW2 HW2A HW2B OW3 HW3A HW3B OW4 HW4A HW4B