Inorganic–Organic Heteropolyacid–Gold(I) Hybrids: Structures and Catalytic Applications

Abstract

Gold(I)-polyoxometalate hybrid complexes 1-4 ([PPh3AuMeCN]xH4-x SiW12O40, x=1-4) were synthesized and characterized. The structure of the primary gold(I)-polyoxometalate 1 (x=1) was fully ascertained by XRD, FTIR, (31)P and (29)Si magic-angle spinning (MAS) NMR, mass spectroscopy, and SEM-energy dispersive X-ray spectroscopy (EDX) techniques. Moreover, this complex exhibited better catalytic activity and selectivity compared with standard, homogeneous, gold catalysts in the new rearrangement of propargylic gem-diesters.

Intramolecular Anion Effect in Polyoxometalate‐Based Organocatalysts: Reactivity Enhancement and Chirality Transfer by a Metal Oxide–Organic Cation Interaction

“…Indeed, POMs are polyanionic molecularly defined clusters of early transition metals and oxygen 1. They are thus suitable ligands for transition metals,2 or supports for active species in heterogeneous catalysis, for example, Lewis acidic cations2b, 3 or organic chiral acids 4. Of particular interest are the reports by the Neumann group, in which a redox active POM supports a metal catalyst by electrostatic interactions and leads to cooperative catalysis 5…”

Polyoxometalate-Gold(I)/H+ Complexes: Air-Stable, Efficient, Polyvalent, and Bifunctional Catalysts

“…10 In this area, we have recently demonstrated that gold(I) cations were effectively very good candidates in constructing type III organic−inorganic complexes. 11,12 Moreover, depending on the applied stoichiometry (x, Scheme 1), excellent and new gold reactivities have been obtained using such [(Ligand)Gold(I)-(Solvent)] +…”

Synthesis, Characterization and Catalytic Activity of NHC Gold(I) Polyoxometalate Complexes

“…Reported gold POM compounds made from inorganic gold salts often display limited stability with undesired reduction into gold nanoparticles . Recently, Nomiya and our group have described two series of redox stable gold(I)‐phosphane POM hybrid materials (type III) made with the cationic [Au(PPh 3 )(MeCN) + ] fragment or the [{Au(PPh 3 )} 4 ( μ 4 ‐O) [2]+ ] cluster .…”