Palladium(ii)-catalyzed substrate-controlled diastereoselective formal (3 + 3) allylic annulation of 2- or 3-substituted 4-hydroxy-but-2-en-1-yl acetates

Abstract

We report a palladium(II)-catalyzed (3 + 3) allylic annulation between 2-(1-alkynyl)-2-alken-1-ones and 2- or 3-substituted (Z)-4-hydroxy-but-2-en-1-yl acetates. This substrate-controlled method for the formation of constitutional isomers efficiently delivers a diversity of 7-vinyl-6,7-dihydro-4H-furo[3,4-c]pyran derivatives containing a quaternary or tertiary carbon center with precise regio- and diastereocontrol (dr > 20 : 1).