Tetraphenolate c-methylcaIix[4]resorcinarene as a new heterogeneous phase transfer catalyst for ring-opening of triaryl substituted pyrylium salts in aqueous biphasic medium

摘要

This study reports, for the first time, the application of water-insoluble tetraphenolate c-methylca-lix[4]resorcinarene as an efficient and heterogeneous phase transfer catalyst at room temperature. This supramolecule could facilitate the nucleophilic reactions through the formation of a host-guest complex in the organic-aqueous interfacial layer. Moreover, the recovered catalyst can be used for several times without serious decrease in activity.