Selective catalysis for the oxidation of alcohols to aldehydes in the presence of cucurbit[8]uril

Efficient selectivity for the supramolecular catalysis by cucurbit[8]uril (Q[8]) for the oxidation of aryl, allyl, and alkyl alcohols to corresponding aldehydes by o-Iodoxybenzoic acid (IBX) in aqueous solvent is reported. The relationship between the catalytic ability of Q[8] and the structure of the substrate has revealed that the catalyst prefers aryl and allyl alcohols to alkyl alcohols, and the conversions of most aryl and allyl alcohols have been increased by 30–50% in the presence of Q[8]. The catalytic selectivity suggests that the IBX oxidation proceeds via a stabilized α-Carbanion intermediate and the supramolecular catalysis should be mechanistically related to the electron density and reactivity of the α-Carbanion.

Graphical abstractEfficient selectivity for the supramolecular catalysis by cucurbit[8]uril (Q[8]) on the IBX oxidation of alcohols to the corresponding aldehydes in aqueous solvent has been investigated.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► We extend our original work about cucurbit[8]uril-catalytic oxidation of benzylic alcohols. ► We investigated universality and selectivity of the Cucurbit[8]uril-catalytic IBX oxidation of various alcohols involving aryl alcohols, allyl alcohols and alkyl alcohols. ► A plausible mechanism of this supramolecular catalysis has been proposed.