Organocatalytic Morita–Baylis–Hillman/Michael/Acetalization Cascade: Procedure‐Controlled Diastereodivergence in the Asymmetric Synthesis of Fully Substituted Tetrahydropyrans

Modulating the diastereoselectivity of stereochemically complex molecules in asymmetric synthesis remains a challenge, especially when the reaction cycle produces no net change in the catalysts, ligands, substrates or additives. Here we accomplish a controlled diastereodivergence in the asymmetric synthesis of fully functionalized tetrahydropyrans by adjusting the sequence of an organocatalytic cascade reaction. We also show that this one‐pot operation provides two synthetically important architectures with excellent stereocontrol. To the best of our knowledge, this is the first published kinetic resolution of MBH alcohols in an organocascade. magnified image