A new nitrile-tethered pyridinium polyoxometalate (POM) was prepared by anion-exchange of the ionic liquid precursor [N-butyronitrile pyridine]Cl ([C 3 CNpy]Cl) with the Keggin phosphovanadomolybdic acid H 5 PMo 10 V 2 O 40 (PMoV 2 ), and the obtained organic POM salt [C 3 CNpy] 4 HPMoV 2 was characterized by XRD, SEM, TG, 1 H NMR, 13 C NMR, ESI-MS, CHN elemental analysis, nitrogen sorption experiment, and melting point measure. When used as a catalyst, [C 3 CNpy] 4 HPMoV 2 causes the first example of reactioncontrolled phase-transfer hydroxylation of benzene with H 2 O 2 , showing high activity and stable reusability. Based on spectral characterizations and comparisons of reaction results, plus the reversible color change between fresh and recovered catalyst, a unique reaction mechanism is proposed for understanding the highly efficient [C 3 CNpy] 4 HPMoV 2 -catalyzed phase-transfer catalysis. The formation of dissolvable active species [VO(O 2 )] + is responsible for the phase-transfer behavior, while the intramolecular charge transfer and the protonated nitrile in cations accelerate the reaction and favor a better catalyst recovery rate.

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Acid–base bifunctional ionic hybrids were employed as catalysts for glucose dehydration to HMF via a unique sequential hydrogen transfer route.

A mesostructured ionic liquid–polyoxometalate (IL‐POM) hybrid has been prepared through designing a new dihydroxy‐tethered guanidinium‐based IL, N′′‐(2,3‐dihydroxypropyl)‐N,N,N′,N′‐tetramethylguanidinium chloride, to interact with Keggin‐type POM phosphotungstic acid (H3PW) in a self‐assembly process. Scanning electron microscopy and transmission electron microscopy showed its special coral‐shaped micromorphology. Nitrogen sorption analysis indicated the formation of a porous structure with a moderate surface area of about 30 m2 g−1 and narrowly distributed pore size located in the mesoscale. Assessed in the cis‐cyclooctene epoxidation with H2O2, the mesostructured hybrid exhibited superior heterogeneous catalytic activity and steady reusability, and the conversion was more than four times that of homogeneous H3PW itself, and more than 14 times that of the nonporous analogues. On the basis of the experimental results, a unique “substrate–solvent–catalyst” synergistic mechanism is proposed and discussed for understanding the dramatically enhanced catalytic performance.

A group of ionic liquid (IL)-based polyoxometalate (POM) salts were prepared via anion-exchange of imidazolium IL precursors tethered by different carbon chain alkyls with various Keggin POMs. The resultant imidazolium POM salts were tested as the catalysts for oxidation of sulfides with aqueous H 2 O 2 . For understanding the POM salt-catalyzed oxidation of sulfides, catalyst compositions, substrates, and reaction conditions were changed. The results show that the imidazolium POM salts are very active and selective heterogeneous catalysts for oxidations of sulfides, adding the advantages of convenient recovery, steady reuse, simple preparation, and flexible composition. Characterizations by Fourier transform infrared (FT-IR), ultraviolet− visible (UV−vis), X-ray diffraction (XRD), and elemental analysis further reveal that the heterogeneous nature of the oxidation processes associates with the good crystallinities of the butyl-and hexyl-functionalized imidazolium POM salts and the hydrogen bonding networks among cations and anions. The POM salts' excellent performances arise from the promoted redox property of the POM-anions by the intramolecular charge transfer from the IL-cations.