Structural and reactivity insights into covalently linked Cu(i) complex-Anderson polyoxometalates

Abstract

The synthesis, crystallographic analysis and full characterization of the Cu(i) complex-functionalized Anderson polyoxomolybdate anions (BuN)[MMoO((OCH)CNCH(CHNPOCu))] (M = Mn, Fe, Co) is reported. For the first time, direct crystallographic evidence for the covalent attachment of a photoactive metal complex to an organo-functionalized polyoxometalate is obtained. Initial electrochemical and photochemical studies report fundamental properties and solution stability of the compounds.

Two Keggin-Based Isostructural POMOF Hybrids: Synthesis, Crystal Structure, and Catalytic Properties

“…POMs due to their anionic nature and ligating oxygens are well-known inorganic ligands and act as building units of such hierarchical structures based on organic ligands and cationic secondary metal ions through covalent or noncovalent linkages. − The design of the organic ligands, the structural nature of the POM, and the coordination geometry of the secondary metal ions are the primary structure directing agents in the design of these hybrids. The use of organic ligands and secondary metal ions often enhances the rich redox chemistry of POMs through synergistic interactions to improve mechanical and chemical stability, solubility, surface area, catalytic site segregation, electronic contributions, and photophysical and electrochemical effects. − Most of the POMOFs reported have exploited primarily two classes of classical heteropolyacids (HPAs) or their close derivatives, specifically, the Keggin (XM 12 O 40 n – ) and the Wells–Dawson units (X 2 M 18 O 62 n – ). , However, recently there have also been several reports of other POMs (classical/nonclassical) used in extended or molecular frameworks (0D/1D/2D), e.g., basketlike POMs, P 6 Mo 18 O 73 , Anderson (XM 6 O 24 n – ) decavanadate (V 10 O 28 6– ) …”

“…24−27 Most of the POMOFs reported have exploited primarily two classes of classical heteropolyacids (HPAs) or their close derivatives, specifically, the Keggin ( X M 1 2 O 4 0 n − ) 2 5 a n d t h e W e l l s − D a w s o n u n i t s (X 2 M 18 O 62 n− ). 27,28 However, recently there have also been several reports of other POMs (classical/nonclassical) used in extended or molecular frameworks (0D/1D/2D), e.g., basketlike POMs, 28 P 6 Mo 18 O 73 , 29 Anderson (XM 6 O 24 n− ) 30 decavanadate (V 10 O 28 6− ). 31 POMs or POMOFs have been used as highly efficient catalysts for different catalytic reactions like acid-catalyzed reactions, selective oxidations, hydrogenation reactions, and also for industrial catalysis because of their oxygen-rich surface, nanodimensions, Bronsted acidity, and redox facile nature.…”