Abstract
The scope of the Lewis acid catalyzed cyclocondensation reaction of activated dienes and aldehydes has been investigated. With a 3-(trialkylsilyl)oxy group in the basic diene, the reaction has been shown to be feasible with 1,1-dimethoxy, 1-(silyloxy)-1-alkyl, and 1-alkyl substituents. Rapid and general routes to various derivatives of 4-pyranone are thus available. © 1984 American Chemical Society.