Cu-Catalyzed Enantioselective Borylative Desymmetrization of 1-Vinyl Cyclobutanols and Axial-to-Point Chirality Transfer in a Diastereoconvergent/Stereoretentive Allylation Scenery.

ABSTRACT

Cu-catalyzed asymmetric allylic borylation of 3,3'-disubstituted 1-vinylcyclobutan-1-ols renders axially chiral allylborane systems, with high asymmetric induction for both enantiomers, by precise selection of the cis or trans substrate. The enantioenriched alkylidenecyclobutanes served as chiral platform to prove the conceptually challenging transference of the axial-to-point chirality through two new stereocenters and one pseudoasymmetric carbon generated via diastereoconvergent allylation of aldehydes, without enantioselective erosion.