Asymmetric syn-1,3-Dioxane Construction via Kinetic Resolution of Secondary Alcohols Using Chiral Phosphoric Acid Catalysts

Herein, we present a novel enantioselective hemiacetalization/intramolecular oxy-Michael addition cascade for the synthesis of syn-1,3-diol frameworks via kinetic resolution of chiral secondary alcohols using chiral phosphoric acid catalysts. By utilizing the recovered optically active starting material, both enantiomers of the corresponding protected 1,3-diols could be obtained with high optical purities. In addition, the products with a carbonyl group were converted diastereoselectively to longer optically active 1,3-polyols, which are representative motifs in polyketides. Moreover, the organocatalytic approach presented in this study facilitates a library construction of useful chiral building blocks for the asymmetric synthesis of bioactive compounds.