Merging Organometallic Chemistry with Polyoxometalate Chemistry

Abstract

A series of polyoxomolybdate-incorporated organometallic complexes has been obtained by reaction of [MBr(CO)5] or solvated M(CO)3+ ions (M = Mn or Br) with (nBu4N)2[Mo2O7] in methanol, sometimes in the presence of triols of the type RC(CH2OH)3 (R = Me or CH2OH). Their molecular structures are related to those of previously described polyoxoalkoxomolybdates through the formal replacement of fac-MoO2(OR)+ units by topologically equivalent fac-M(CO)3+ units. Representative pairs of structurally related clusters include [Mo2O6(OMe)4-Re(CO)32]2- and [Mo4O10(OMe)6]2-, [Mo2O4MeC(CH2O)32Mn(CO)3]- and [Mo3O6(OMe)MeC(CH2O)32]-, [Mo2O4HOCH2C(CH2O)32Mn(CO)32] and [Mo4O8(OEt)2MeC(CH2O)32], [Mo6O16(OMe)2MeC(CH2O)32-Mn(CO)32]2- and [Mo8O20(OMe)4-MeC(CH2O)32]2-. Although the frameworks of the majority of derivatives are based on tetranuclear units which display the common rhomb-like structure, the alternative cubane-type arrangement is observed in [Mo2O5(OMe)5M(CO)32]-.

A Basket‐Like [Sr⊂P6MoV4MoVI14O73]10– Polyoxoanion Modified with {Cu(phen)(H2O)x} (x = 1–3) Fragments: Synthesis, Structure, Magnetic, and Electrochemical Properties

“…These kinds of modified POM derivatives can be regarded as an ideal molecular model for determination of the mechanisms of oxide‐supported catalysts 1. Furthermore, such kinds of compounds can be molecularly fine‐tuned and provide potentially new types of catalyst systems as well as interesting functional materials with optical, electronic, and magnetic properties 1b,1c. During the preparation, two strategies have been exploited to increase the surface charge density and activate the surface oxygen atoms of heteropolyoxoanions:1 (1) reduce the metal centers from a high oxidation state to a low oxidation state, for example, from Mo VI to Mo V , by introducing strong reducing reagents or (2) replace high‐valence metal centers with lower‐valence ones, for instance, from Mo VI to V IV or TM 2+ (TM = transition metal).…”

Ratio-Controlled Precursors of Anderson–Evans Polyoxometalates: Synthesis, Structural Transformation, and Magnetic and Catalytic Properties of a Series of Triol Ligand-Decorated {M2Mo6} Clusters (M = Cu2+, Co2+, Ni2+, Zn2+)

“…That means that each {MoO 6 } octahedron possesses no more than two unshared terminal O atoms. − However, these types of clusters can be synthesized by coordination with organic ligands to reduce the number of unshared terminal O atoms , and finally assemble into a ring architecture . The triol ligand is demonstrated to have an ideal coordination form to stabilize the {Mo 2 O 10 } cluster through its three O atoms, forming a doubly triol-ligand-decorated {Mo 2 O 10 } cluster. , The modification makes it possible for this cluster to serve as a building block for further assembly with other metal ions . Following our previous studies on the decoration fashions of Anderson–Evans cluster hybrids by changes in the starting materials, , we speculate that there should be triol-ligand-decorated {Mo 2 O 10 } clusters during the preparation process, and they could act as independent precursors for coordination with metal ions.…”

Bioorthogonal chemistry of polyoxometalates – challenges and prospects

“…Hybrid organic-inorganic polyoxometalate (POM) compounds 7,8 combine a discrete, nanosized metal-oxo core exhibiting rich redox chemistry and catalytic activity with an organic environment that does not only stabilize these molecular metal oxides and improves their solubility in various media, but can also empower the physicochemical properties to the POM due to synergistic effects. Organic ligation serves as a platform for functionalization and post-functionalization strategies, [9][10][11][12] providing chemists with the ability to tailor a wide variety of molecular architectures. The latter include numerous conjugates with biological molecules.…”