Palladium-catalyzed oxidative cycloaddition of 1-indanones and internal aryl alkynes toward benzo[c]fluorenone derivatives

The palladium-catalyzed dehydrogenative [4+2] annulation of 1-indanones with alkynes has been reported. In this protocol, the palladium-catalyzed desaturation of 1-indanones to indenones occurs, followed by the palladium catalyzed oxidative cyclization of indenones with alkynes, generating diverse benzo[c]fluorenone derivatives in satisfactory yields and regioselectivity.