Increased formation of oxepanes in non-aqueous medium in the cycloaddition of 3-O-allyl-1,2-isopropylidenefuranose N-Ph nitrones

Cycloaddition of 3-O-allyl-1,2-isopropylidene N-Ph nitrones afforded appreciably increased yields of oxepanes compared to the corresponding N-Me or N-Bn nitrones. Higher yields permitted some useful further transformations of the oxepanes.