Copper-catalyzed intramolecular hydroalkoxylation of α-(1-hydroxy-1-alkyl- and -aryl)methylallenoates by a 5-endo mode for preparation of 2-alkyl- and 2-aryl-2,5-dihydrofurans.

Ethyl α-(1-hydroxy-1-alkyl)methylallenoates and α-(1-hydroxy-1-aryl)methylallenoates containing not only electron-donating groups but also an electron-withdrawing group on the aryl group at the α-position have been shown to undergo an efficient and selective copper-catalyzed intramolecular hydroalkoxylation to give functionalized 3-ethoxycarbonyl-2-alkyl- and -aryl-2,5-dihydrofurans in good to excellent yields through a 5-endo mode.