Gold-catalyzed π-directed regioselective cyclization of bis(o-alkynyl benzyl alcohols): rapid access to dihydroisobenzofuran derivatives†
Abstract
Herein we demonstrate a gold-catalyzed regio- and stereo-selective cycloisomerization of bis(o-alkynyl benzyl alcohols). By this protocol, the synthesis of dihydroisobenzofuran derivatives can be achieved in good yields. The reaction features a continuous alkyne/alkene-directed 5-exo-dig cyclization and a Prins-type cyclization for the formation of three cycles.