A Novel Palladium-Mediated Cascade Reaction Triggered by Strain Release of the Cyclobutane System. A New General Route to Benzo- and Naphthohydrindans

A novel palladium-mediated cascade reaction was reported. By this procedure, the olefinic cyclobutanols 17, 24, and 31; 41; 37; and 45 afforded the benzo- and naphthohydrindans (46−49, 50−53, 54−57, and 58−61) respectively in one operation in the ratios depending on the mediators and solvents employed. This provides a novel and efficient synthesis of biologically important A-nor and C₁₁-alkylated steroids.