Self-Assembly of Hybrid Organic−Inorganic Polyoxomolybdates: Solid-State Structures and Investigation of Formation and Core Rearrangements in Solution

Abstract

We report here a facile synthetic and analytical approach that allows us to identify and characterize functionalized polyoxomolybdate clusters that form upon the partial reduction of Mo(VI) salts in the presence of organoarsonate ligands. We demonstrated that electrospray ionization mass spectrometry, in combination with X-ray crystallography, provides an extremely powerful tool, allowing us to exploit slight perturbations of the ligand structures for the preparation of a series of unprecedented cluster compounds. Redox-active transition metals that adopt cubane or related structures are of particular interest because of their resemblance to active sites of enzymes. Our investigations underline the stability of the hybrid compounds in solution, an essential requirement for potential applications as catalysts. Supplemental analyses include measurements of the magnetic properties, NMR, IR, UV/vis, and bond-valence-sum analyses. Our results highlight the possibility of exploring real-time growth reactions of polyoxometales that emerge in solution and transform to produce hybrid organic-inorganic polyoxometalate clusters.

Introducing Chirality into Hybrid Clusters from an Achiral Ligand: Synthesis and Characterization of Polyoxomolybdates Containing a Benzylarsonate Group

“…In contrast, cluster 2a [(C 6 H 5 CH 2 AsO 3 ) 4 Mo 12 O 34 ] 4– is revealed to be a classic “inverse‐Keggin” cluster, in which the tetrahedral {RAsO 3 } units are located on the surface of the cluster . The main body of the cluster is nearly identical to reported analogues with the exception of the organic group .…”

Tetrabutylammonium hydrogen phenylarsonate–phenylarsonic acid (1/1)

“…For hybrid organic-inorganic polyoxidometalate frameworks including arylarsonic acid ligands, see: Breen, Clé rac et al (2012) ;; ; Onet et al (2011); Breen & Schmitt (2008 Table 1 Selected bond lengths (Å ). Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008) and OLEX2 (Dolomanov et al, 2009); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and OLEX2; molecular graphics: OLEX2; software used to prepare material for publication: SHELXL97 and OLEX2.…”

“…In the course of our studies on hybrid organic-inorganic polyoxometalate frameworks, including arylarsonic acid ligands (Breen, Clérac et al, 2012;Onet et al, 2011;Breen & Schmitt, 2008), we attempted to prepare tetrabutylammonium hydrogen phenylarsonate [(C 4 H 9 ) 4 N] + [C 6 H 5 AsO 3 H] -as a starting material for synthesis. Unexpectedly, mixing equimolar amounts of tetrabutylammonium hydroxide and phenylarsonic acid in aqueous solution and slow evaporation resulted in crystals with a 2:1 stoichiometry of tetrabutylammonium to phenylarsonic acid.…”

Photoluminescent lead(II) coordination polymers stabilised by bifunctional organoarsonate ligands

“…So far, reports on metal arsonates are rather scarce. Most of the reported metal organoarsonates are hybrid polyoxometalate (POM) clusters based on V, Mo, or W [41–52]. In particular, Zubieta’s research group has extensively explored the formation of such hybrid POMs [45, 47, 48, 50, 51].…”