Direct Access to 2,3,4,6-Tetrasubstituted Tetrahydro-2H-pyrans via Tandem SN2'-Prins Cyclization.
Jimena ScocciaSixto J PérezVictoria SinkaDaniel A CruzJuan M López-SoriaIsrael FernándezVíctor S MartínPedro O MirandaJuan I PadrónPublished in: Organic letters (2017)
A new, direct, and diastereoselective synthesis of activated 2,3,4,6-tetrasubstituted tetrahydro-2H-pyrans is described. In this reaction, iron(III) catalyzed an SN2'-Prins cyclization tandem process leading to the creation of three new stereocenters in one single step. These activated tetrahydro-2H-pyran units are easily derivatizable through CuAAC conjugations in order to generate multifunctionalized complex molecules. DFT calculations support the in situ SN2' reaction as a preliminary step in the Prins cyclization.