π4s+π2s Cycloaddition between electron deficient π-systems and photoreaction of β,γ-enones: a novel stereoselective entry into angular triquinanes

Cycloaddition of electron deficient partners such as cyclohexa-2,4-dienone and acrylates leading to an efficient synthesis of complex bicyclo[2.2.2]octenones having a β,γ-enone chromophore, and their transformation to angular triquinanes via photoreaction, is described.