P–C Bond Cleavage-Assisted Lanthanide Phosphate Coordination Polymers

Abstract

The reaction of lanthanide­(III) salts with an organodiphosphonic acid under hydrothermal conditions resulted in a P–C bond cleavage affording [{Eu4(PO4)­(PO4)0.5×4(PO4)0.25×4(H2O)2}·6H2O] n (1), [{Dy4(PO4)­(PO4)0.5×4(PO4)0.25×4(H2O)2}·6H2O] n (2), and [{Gd­(PO4)0.5(PO4)0.5(H2O)3}·2H2O] n (3). 1 and 2 are porous 3D coordination polymers whose repeating units possess a dimeric motif. While one lanthanide ion in the dimer is eight-coordinate in a distorted square-antiprismatic geometry, the other is nine-coordinate and present in a distorted monocapped square-antiprismatic geometry. In contrast to 1 and 2, 3 possesses a 2D architecture; the asymmetric unit contains a monomeric GdIII center which is nine-coordinate in a distorted monocapped square-antiprismatic geometry.

Pentanuclear Lanthanide Mono-organophosphates: Synthesis, Structure, and Magnetism

“…However, in the case of organophosphate esters, the situation is more complicated by the inherent ability of lanthanide ions to hydrolyze and cleave the ester P–O bonds, leading to the formation of insoluble inorganic phosphates . Interestingly, metal ions have also been reported to cleave the P–C bond in the case of organophosphonates under solvothermal reaction conditions . Thus, in order to prevent hydrolysis in the course of the reaction, we have precisely selected a sterically encumbered monoester of phosphoric acid, namely, 2,6-diisopropylphenyl dihydrogen phosphate (dippH 2 ), where the isopropyl groups impart additional solubility and provide a protective hydrophobic pocket near the hydrolytically susceptible P–O bond of the ester.…”

Rare Examples of Amine-Templated Organophosphonate Open-Framework Compounds: Combined Role of Metal and Amine for Structure Building

“…Investigation of a new open-framework structure by the assemblage of hybrid inorganic–organic building blocks is a subject of intense research in material chemistry for the past four decades, resulting in various applications such as proton conductors, catalysts, ion-exchangers, sensors, sorbents, charge storage materials, and so on. − Although the initial research of zeolite based open-frameworks focused on silicate and phosphate based networks, later on, phosphite, sulfate, sulfite, selenate, selenite, and borate based framework structures were also investigated in large numbers. − Exploration and incorporation of newer anions as network builders is a major enduring challenge; the successful discovery of new frameworks with the thiosulfate unit is an example in our earlier work. − The selection of new building blocks with inorganic–organic moieties can combine the coordination versatility of the inorganic along with the functional diversity of the organic group. Hence, organophosphonate could be a possible replacement for the traditional inorganic phosphate unit.…”

Interpenetrated and Catenated Zinc Thiosulfates Frameworks with dia and qtz Nets: Synthesis, Structure, and Properties

“…To the best of our knowledge, this is the first observation of catenated layered structure involving thiosulfate hybrids. In addition, it may be noted that the structure of I has the basic building unit, the four-membered ring, formulated to be the fundamental building unit in the tetrahedral structures of aluminosilicate and aluminophosphates. − The observation of the simple four-membered ring structure in the present compounds suggests that it may be possible to prepare compounds that are similar to the phosphates and silicates. − …”

“…Phosphate and silicate based framework compounds, with interconnected channels and cavities, have been investigated extensively for their many applications in the area of catalysis, luminescence, sorption, and separation processes. − The new family of framework compounds based on carboxylates, known as metal–organic frameworks (MOF) or inorganic coordination polymers (CP), are being studied vigorously during the past two decades for their many potential applications in sorption and catalysis. − The studies on MOFs and related compounds have brought out the usefulness of nitrogen containing aromatics as ligands and structure builders. − The usefulness of 4,4′-bipyridine in extending the dimensionality of the structure was established during the preparation of phosphates and related structures. − This strategy was also adapted for the preparation of many other compounds. − …”