FeCl3-catalyzed tandem Prins and Friedel–Crafts cyclization: a highly diastereoselective route to polycyclic ring structures

Abstract

Catalytic FeCl3 in the presence of 4Å molecular sieves has been shown to effect highly diastereoselective tandem Prins and Friedel–Crafts cyclization of substituted (E/Z)-6-phenylhex-3-en-1-ol and a variety of aldehydes to provide a range of polycyclic compounds in good to excellent yields. The reaction of an enantioenriched alcohol with an aldehyde provided the cyclization product without loss of optical activity. Furthermore, a Lewis acid catalyzed ring opening resulted in functionalized tetralin derivatives with multiple chiral centers.