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-lodoxybenzoic 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 alpha-Carbanion intermediate and the supramolecular catalysis should be mechanistically related to the electron density and reactivity of the alpha-Carbanion. (C) 2011 Elsevier B.V. All rights reserved.