An unprecedented protocol has been developed for the regioselectivesynthesis of structurally diverse indene derivatives from readily accessible N-benzylic sulfonamides and disubstituted alkynes through FeCl3-catalyzed cleavage of sp3 carbon−nitrogen bonds to generate benzyl cation intermediates. In the presence of 10 mol % of FeCl3, a broad range of N-benzylic sulfonamides smoothly react with internal
Development of a CuCl/phosphine system to catalyze phenylation and methylation of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>N</mml:mi></mml:math>-tosyl aldimines with phenylboronic and methylboronic acids
A range of arylallenes undergo carbocation-initiated cyclization reaction with N-benzylic and N-allylic sulfonamides in the presence of 10 mol% ferric chloride to give structurally diverse polysubstituted indenes in good yields with extremely high regioselectivity.