A simple and convenient synthetic approach to difurylmethane derivatives has been developed via gold-catalyzedcycloisomerization of 1-oxiranyl-2-alkynyl esters and dimerization of the 2-(α-hydroxyalkyl)furans. The reaction takes place in the presence of 2 mol% of tetrachloroauric acid tetrahydrate (HAuCl4⋅4 H2O) under very mild conditions.
A novel gold-catalyzed tandem cyclization/[1,2]-alkyl migration process of epoxy alkynes to spiropyranones has been discovered. From this process, the construction of adjacent multiple stereocenters with a new quaternary carbon atom is achieved. The gold-catalyzeddominoprocess is stereospecific with respect to the migrating carbon atom. A type of unusual C-C bond cleavage of epoxide systems has also