Stereoretentive Protection and Deprotection of Chiral Silanol

In this study, we demonstrate that allylic groups serve as versatile protective groups for the hydroxy group of chiral silanols. The protection and the deprotection are accomplished through Williamson‐type etherification and the Tsuji–Trost‐type reaction, respectively, in a highly stereoretentive manner. Furthermore, we found that a benzylic ether can be used as an orthogonal protective group to allyl protection. Using them, we achieved enantiodivergent synthesis of a chiral alkoxysilanol from one enantiomer of chiral dialkoxysilane.