Assembly of a Hexameric Cluster of Polyoxomolybdotriphosphonate Builts from [Zn(H₂O){TeMo₆O₂₁}{N(CH₂PO₃)₃}]^6– Subunits and Its Optical and Catalytic Properties

Abstract

The crown-shaped organotriphosphonate-modified 36-molybdenum cluster (NH4)18­Na7H11­[Zn­(H2O)­TeMo6O21­{N­(CH2PO3)3}]6·23H2O (1) has been synthesized, which is the largest zinc-containing organophosphonate-based polyoxometalate to date. Compound 1 was prepared in buffer solution (pH 5.5) with heptamolybdate and amino trimethylene phosphonic acid (ATMP) as the organic ligand. The polyanion constructed from a hexmeric assembly of [Zn­(H2O)­{TeMo6O21}­{N­(CH2PO3)3}]6– subunits has been fully investigated by a few characterization methods. In this work, we discovered that 1 exhibited reversible photochromism and it changed from white to reddish brown upon UV irradiation. In addition, compound 1, as a catalyst, can oxidize sulfides to sulfoxides, showing a high yield/conversion and a good selectivity.

Rational design and progress of molybdenum-oxo clusters

“…Firstly, polyanions as building units, metal ions and ligands as linkers to form wheel–like structures. In 2020 and 2021, the Niu group reported on three organophosphate – modified molybdenum wheels, 80–82 namely X[M(H 2 O)TeMo 6 O 21 {N(CH 2 PO 3 ) 3 }] 6 · n H 2 O (M = Cu, X = (NH 4 ) 19 Na 7 H 10 , n = 31; M = Co, X = (NH 4 ) 17 Na 7 H 12 , n = 42; M = Zn, X = (NH 4 ) 18 Na 7 H 11 , n = 23). A large [Co(H 2 O)TeMo 6 O 21 {N(CH 2 PO 3 ) 3 }] 6 36− polyanion was constructed by six ATMP (amino trimethylene phosphonic acid), six cobalt atoms and six {TeMo 6 O 21 } build units, with the two {PO 3 } groups bonded with four {MoO 6 } octahedrons.…”

“…145–147 A series of molybdenum clusters with obvious photochromism were reported by the Niu group. 76,82 In 2015, three molybdenum clusters with {TeMo 6 O 21 } as building blocks were reported. 76 These complexes changed from white to reddish brown over time (under the irradiation of a Xe lamp), and the color change rate of this complex is significantly slower than other complexes.…”

A series of POM compounds constructed using a flexible ligand containing three coordination groups: electrocatalytic and photocatalytic reduction and amperometric detection of Cr(vi)

“…Polyoxometalates (POMs), as metal-oxo clusters with rich structures and various properties, have been widely used in many fields such as electricity, optics, catalysis, and materials. 1–9 The combination of POMs as inorganic units and transition metal complexes (TMCs) can form a variety of structures. 10 Moreover, the selection of appropriate organic ligands is very important for the construction of POM–TMC structures.…”

Four POM-based complexes modified by multi-nuclear clusters: structure, photocatalytic, supercapacitor and chromogenic properties

“…Chromogenic materials, such as photochromic and thermochromic materials, have become the subject of extensive research and have a wide range of applications in the fields of eyeglass lenses, printing, sensors and optical data storage. 24–26 However, the photochromic and thermochromic materials based on POMs were rarely reported. In 2014, Wang et al 27 synthesized a series of rare earth complexes, showing a color change from white to deep blue (almost black) with increasing irradiation time.…”