Access to Polycyclic Derivatives by Triflate-Catalyzed Intramolecular Hydroarylation

An efficient and versatile synthesis of indane, tetralin and benzosuberan derivatives has been developed; the synthesis starts from nonactivated aromatic compounds bearing unsaturated side chains and is a bismuth(III) or indium(III) trifluoromethanesulfonate-catalysed atom-economic process. A variety of polycyclic compounds have been isolated in high yields. Lactonisation could be observed for esters with 2,2-disubstituted terminal olefins through a Lewis acid catalysed reaction between the olefin and one of the ester groups.