Heteroleptic LaIII Anilate/Dicarboxylate Based Neutral 3D-Coordination Polymers

Abstract

Three new 3D metal–organic frameworks of lanthanum based on mixed anionic ligands, [(La2(pQ)2(BDC)4)·4DMF]n, [(La2(pQ)2(DHBDC)4)·4DMF]n, [(La2(CA)2(BDC)4)·4DMF]n (pQ—dianion of 2,5-dihydroxy-3,6-di-tert-butyl-para-quinone, CA—dianion of chloranilic acid, BDC-1,4-benzenedicarboxylate, DHBDC-2,5-dihydroxy-1,4-benzenedicarboxylate and DMF-N,N′-dimethylformamide), were synthesized using solvothermal methodology. Coordination polymers demonstrate the rare xah or 4,6T187 topology of a 3D framework. The homoleptic 2D-coordination polymer [(La2(pQ)3)·4DMF]n was obtained as a by-product in the course of synthetic procedure optimization. The thermal stability, spectral characteristics and porosity of coordination polymers were investigated.

Glycols in the Synthesis of Zinc-Anilato Coordination Polymers

“…Meanwhile, the thermal behavior of compound 3 is comparable to the data obtained for 2D grids based on lanthanide ions [26] with the same ligands. When comparing glycol-containing polymers 1 and 2 with complex 3, it is unambiguously possible to conclude that the hydroxyl-containing ligand promotes the dealkylation of the anilate ligand at sufficiently low temperatures, which was not observed in other studied derivatives based on this para-quinone ligand [26][27][28].…”

“…In this regard, the study of new ancillary ligands with various substituents in the quinoid ring is one of the promising tasks for expanding the range of properties of redox-active MOFs [4,23,24]. The study of 2,5-dihydroxy-3,6-di-tert-butyl-para-quinone (H 2 pQ) [25] as a ditopic ligand in the synthesis of metal-organic frameworks started recently [26][27][28]. Previously, mononuclear derivatives of triphenylantimony(V) [29] and rare binuclear complexes of tin, nickel, iron, and cobalt with this ligand were already known [25,30,31].…”

“…It changes the polymer structure and affects the physicochemical properties of the resulting derivative. For example, intensive research has begun on the properties of heteroleptic derivatives containing simultaneously two types of ligands in the MOF: anilate and dicarboxylate [27,32,33]. The recent works [34,35] demonstrated the use of polyatomic alcohols as anionic ligands in the synthesis of heteroleptic zinc MOFs.…”

Structural diversity of cadmium coordination polymers based on an extended anilate-type ligand

“…Coordination polymerbased materials can serve as gas adsorbents, [46][47][48] luminescent agents, 9,49 electrochemical or photophysical sensors, 4,50 and electroconductive 5,[51][52][53][54][55][56][57][58] and magnetic materials. 29,59,60 The creation of new anilate-type ligands for the synthesis of CPs, 3,44,59 as well as the preparation of mixed-ligand CPs containing two anionic ligands, 49,[61][62][63][64][65][66][67] is a promising area of research, as it opens the possibility of synthesizing compounds with new topologies and properties. One of the prospective ditopic ligands for the synthesis of new derivatives is the closest analog of anilate ligands containing an extended π-system -4,4′-(1,4-phenylylenebis(azanylylidene))bis (3,6-di-tertbutyl-2-hydroxycyclohexa-2,5-dienone) (H 2 L).…”

Construction of Two Stable Co(II)-Based Hydrogen-Bonded Organic Frameworks as a Luminescent Probe for Recognition of Fe3+ and Cr2O72− in H2O

“…HOFs have attracted a significant deal of attention especially because of their broad applications, ranging from chemical sensing [ 6 ] and bioimaging [ 7 , 8 ] to lighting [ 9 ] and 3D optical storage [ 10 , 11 ]. The metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) are usually connected by coordination bonds or covalent bonds between atoms and show relatively high stabilities [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ], while the HOFs are linked by weak non-covalent interactions, such as hydrogen bonds and π−π stacking interactions, and exhibit relatively low stabilities [ 21 , 22 , 23 , 24 , 25 ]. For HOFs, the solvent guests play important roles in the construction of the supermolecular network system.…”