Initial Steps of the Acid-Catalyzed Polyoxometalate-Functionalization with Phosphonic Acid Esters

The organo-functionalization of metal oxides is a key strategy to introduce new functionalities. Often, phosphonates are used to anchor organic moieties to a range of metal oxides. Despite their widespread use, there is a lack of understanding of the parameters which enable selective and efficient formation of organophosphonate-metal oxide hybrids. Here, we report fundamental insights into the mechanism of phosphonate anchoring to a molecular metal oxide model. Specifically, we use in situ 31P NMR spectroscopy to follow the acid-catalyzed deprotection of a model phosphonate and its subsequent condensation to form a phosphonate-functionalized Dawson-polyoxometalate. Our study shows that the nucleophilicity of the acid anion is a key parameter which controls the clean and selective deprotection and polyoxometalate attachment of phosphonates. This insight will allow researchers to expand the scope of phosphonate anchoring to metal oxides by enabling the development of mild and scalable syntheses

“Bottom-Up” Meets “Top-Down” Assembly in Nanoscale Polyoxometalate Clusters: Self-Assembly of [P₄W₅₂O₁₇₈]²⁴⁻ and Disassembly to [P₃W₃₉O₁₃₄]¹⁹⁻

“Bottom-Up” Meets “Top-Down” Assembly in Nanoscale Polyoxometalate Clusters: Self-Assembly of [P4W52O178]24− and Disassembly to [P3W39O134]19−</sup

Heteroatom-Controlled Kinetics of Switchable Polyoxometalate Frameworks

Heteroatom-Controlled Kinetics of Switchable Polyoxometalate Framework

“Bottom-Up” Meets “Top-Down” Assembly in Nanoscale Polyoxometalate Clusters: Self-Assembly of [P₄W₅₂O₁₇₈]²⁴⁻ and Disassembly to [P₃W₃₉O₁₃₄]¹⁹⁻

“Bottom-Up” Meets “Top-Down” Assembly in Nanoscale Polyoxometalate Clusters: Self-Assembly of [P4W52O178]24− and Disassembly to [P3W39O134]19−</sup

Heteroatom-Controlled Kinetics of Switchable Polyoxometalate Frameworks

Heteroatom-Controlled Kinetics of Switchable Polyoxometalate Framework

Unravelling the Complexities of Polyoxometalates in Solution Using Mass Spectrometry: Protonation versus Heteroatom Inclusion

A route to unravel and the complexities of polyoxometalates in solution using electrospray mass spectrometry is presented. This reveals the limited speciation of the clusters in organic solvent compared to that in aqueous solution and allows the unambiguous assignment of the protonation states of the cluster as a function of heteroatom inclusion

Unravelling the Complexities of Polyoxometalates in Solution Using Mass Spectrometry: Protonation versus Heteroatom Inclusion

A route to unravel and the complexities of polyoxometalates in solution using electrospray mass spectrometry is presented. This reveals the limited speciation of the clusters in organic solvent compared to that in aqueous solution and allows the unambiguous assignment of the protonation states of the cluster as a function of heteroatom inclusion

Unravelling the Complexities of Polyoxometalates in Solution Using Mass Spectrometry: Protonation versus Heteroatom Inclusion

A route to unravel and the complexities of polyoxometalates in solution using electrospray mass spectrometry is presented. This reveals the limited speciation of the clusters in organic solvent compared to that in aqueous solution and allows the unambiguous assignment of the protonation states of the cluster as a function of heteroatom inclusion

Unravelling the Complexities of Polyoxometalates in Solution Using Mass Spectrometry: Protonation versus Heteroatom Inclusion

A route to unravel and the complexities of polyoxometalates in solution using electrospray mass spectrometry is presented. This reveals the limited speciation of the clusters in organic solvent compared to that in aqueous solution and allows the unambiguous assignment of the protonation states of the cluster as a function of heteroatom inclusion

Molecular Growth of Polyoxometalate Architectures Based on [−Ag{Mo₈}Ag−] Synthons: Toward Designed Cluster Assemblies

The interaction of silver(I) cations with octamolybdate [Mo8O26]4− has been investigated by applying the principles of the building-block concept to the well established silver−octamolybdate reaction system. The self-assembly of dimeric {Ag2} linkers allows the formation and isolation of chains and networks where [Mo8O26]4− clusters are cross-linked by silver(I) cations. The influence of the solvent on the overall topology has been studied, and the role of the counterion on the resulting structure has been highlighted in each assembly. Fine-tuning of the metal−metal distances of the dimeric {Ag2} linking units has been achieved by using different coordinating solvents which act as bridges. Five compounds based on silver octamolybdate building blocks have been isolated, including an uncommon intermediate ((Ph4P)2[Ag2(CH3CN)2(Mo8O26)]), three one-dimensional polymeric chains ([Ag(C7H12O2N)(CH3CN)]2n[Ag2(CH3CN)2(Mo8O26)]n·2CH3CN, (Ph4P)2n[Ag2(DMF)2(Mo8O26)]n·2DMF, and (H2NMe2)2n[Ag2(DMF)2(Mo8O26)]n·2DMF), and a two-dimensional cross-linked network ([(Ag(DMF))2(Ag(DMF)2)2Mo8O26]n). Each compound has been characterized by single-crystal X-ray diffraction, elemental analysis, and FT-IR