Modular Molecules: Site‐Selective Metal Substitution, Photoreduction, and Chirality in Polyoxometalate Hybrids. Issue 43 (9th September 2014)

• Record Type: Journal Article
• Authors: Vonci, Michele; Akhlaghi Bagherjeri, Fateme; Hall, Peter D.; Gable, Robert W.; Zavras, Athanasios; O'Hair, Richard A. J.; Liu, Yuping; Zhang, Jie; Field, Matthew R.; Taylor, Matthew B.; Du Plessis, Johan; Bryant, Gary; Riley, Mark; Sorace, Lorenzo; Aparicio, Pablo A.; López, Xavier; Poblet, Josep M.; Ritchie, Chris; Boskovic, Colette
• Is Part Of: Chemistry. Volume 20:Issue 43(2014)
• Page Start: 14102
• Page End: 14111
• Publication Date: 2014-09-09
• Subjects: amino acids -- chirality -- electronic structure -- photoreduction -- polyoxometalates; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201403222
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The first members of a promising new family of hybrid amino acid–polyoxometalates have emerged from a search for modular functional molecules. Incorporation of glycine (Gly) or norleucine (Nle) ligands into an yttrium‐tungstoarsenate structural backbone, followed by crystallization with p ‐methylbenzylammonium ( p ‐MeBzNH3 + ) cations, affords ( p ‐MeBzNH3 )6 K2 (GlyH)[As III 4 (Y III W VI 3 )W VI 44 Y III 4 O159 (Gly)8 ‐ (H2 O)14 ]⋅ 47 H2 O (1 ) and enantiomorphs ( p ‐MeBzNH3 )15 (NleH)3 [As III 4 (Mo V 2 Mo VI 2 )W VI 44 Y III 4 O160 (Nle)9 (H2 O)11 ][As III 4 (Mo VI 2 W VI 2 )‐ W VI 44 Y III 4 O160 (Nle)9 (H2 O)11 ] (generically designated 2 : L ‐Nle, 2 a ; D ‐Nle, 2 b ). An intensive structural, spectroscopic, electrochemical, magnetochemical and theoretical investigation has allowed the elucidation of site‐selective metal substitution and photoreduction of the tetranuclear core of the hybrid polyanions. In the solid state, markedly different crystal packing is evident for the compounds, which indicates the role of noncovalent interactions involving the amino acid ligands. In solution, mass spectrometric and small‐angle X‐ray scattering studies confirm maintenance of the structure of the polyanions of 2, while circular dichroism demonstrates that the chirality is also maintained. The combination of all of these features in a single modular family emphasizes the potential of such hybrid polyoxometalates to provide nanoscale molecular materials with tunable properties. Abstract : Modular molecules : The first members of a modular family of hybrid amino acid–polyoxometalates have been investigated by a variety of physical techniques. The apparent site‐selective metal substitution, photoreduction, chirality, and directable solid‐state packing highlight the remarkable tunability of the structural features and ensuing physical properties of this new family of molecules and thus their potential for the development of functional molecular materials (see figure).