A new oxovanadium(IV)–cucurbit[6]uril complex: Properties and potential for confined heterogeneous catalytic oxidation reactions

This work presents a new oxovanadium(IV)–cucurbit[6]uril complex, which combines the catalytic properties of the metal ion with the size-excluding properties of the macrocycle cavity. In this coordination compound, the VO2+VO2+ ions are coordinated to the oxygen atoms located at the rim of the macrocycle in slightly distorted square-pyramidal configurations, which are in fact C2vC2v symmetries. This combination results in a size-selective heterogeneous catalyst, which is able to oxidize linear alkanes like n-pentane at room temperature, but not styrene, cyclohexane or z-cyclooctene, which are too big to enter the cucurbit[6]uril cavity. The results presented here contribute to understanding the mechanism of alkane catalytic oxidation by oxovanadium(IV) complexes.

Graphical abstractThis paper presents a new complex of oxovandium (IV) and cucurbit[6]uril, which combines the catalytic properties of the metal ion with the size-excluding properties of the macrocycle cavity. This combination resulted in a size-selective heterogeneous catalyst, which is able to oxidize at room temperature linear alkanes like n-pentane, but not styrene, cyclohexane nor z-cyclooctene, which are too big to enter the cucurbit[6]uril cavity.Figure optionsDownload full-size imageDownload as PowerPoint slide