Stereoselective Synthesis of Polysubstituted Tetrahydropyrans by Brønsted Acid‐Mediated Hydroxyalkoxylation of Silylated Alkenols

A convenient route for the preparation of tetrahydropyran (THP) derivatives with a quaternary and tertiary vicinal stereocenters is reported. The atom economy acid‐catalyzed cyclization of allylsilyl alcohols provided polysubstituted tetrahydropyrans in good yields and excellent diastereoselectivities (>95 : 5). In comparison with the traditional oxymercuration procedure, this approach resulted to be more efficient in both yield and stereocontrol.