Asymmetric Dihydroxylation-Based Desymmetrization Enabled by Lone-Pair−π Interaction

Lone-pair−π interactions, which form a stabilizing association between a lone pair of electrons and a π system, are widely recognized as supramolecular bonds. However, such noncovalent interactions rarely serve as a key stereocontrolling element in chemical reactions. Herein, we report a well-engineered lone-pair−π interaction-directed catalytic system for asymmetric dihydroxylation (AD)-based desymmetrization. The lone-pair−π interaction between the C9 carbonyl in mono-cinchona alkaloids and the electron-deficient phthalazine in the symmetric alkene substrates was exploited to realize a highly efficient AD-based desymmetrization, which was difficult to execute following the traditional Sharpless asymmetric dihydroxylation method.