A practical and diastereoselective synthesis of dihydrofurocoumarin from pyridinium ylides in aqueous medium

摘要

A series of 2,3-dihydrofurocoumarins were prepared via a three-component reaction of aldehyde, pyridinium salt and 4-hydroxycoumarin in aqueous ethanol. This method avoids using excessive pyridine and trimethylamine, and has operational simplicity and avoids tedious column chromatography purification. Both aryl aldehydes and aliphatic aldehydes are applicable to this protocol.