Enantioselective Desymmetrizing Hydroalkoxylation of 1,4- and 1,8-Diynes Enabled by Chiral Brønsted Acid Catalysis

Herein,
an organocatalytic enantioselective desymmetrizing hydroalkoxylation
of 1,4- and 1,8-diynes is disclosed, which represents a unique chiral
Brønsted acid-catalyzed desymmetrization of diynes. This protocol
provides a facile and practical access to enantioenriched 1,3-diaminopropanol
derivatives and γ-butyrolactones with a wide substrate scope
and generally high enantioselectivities. Besides, the backbones of
these products constitute the structural core of numerous bioactive
molecules, and they can serve as valuable precursors for the expeditious
assembly of versatile N- and O-heterocycles. Moreover, control experiments
and theoretical calculations are employed to confirm the mechanistic
rationale and elucidate the origin of enantioinduction.