Enantioselective Copper-Catalyzed Three-Component Cascade Boronation-Dearomatization Reaction: Synthesis of Chiral Boron-Containing 1,4-Dihydropyridines.

A three-component cascade boronation-dearomatization reaction of alkenes, a diboron compound, and a pyridinium salt is diclosed, affording chiral boron-containing 1,4-dihyropyridines in high yields (≤98%) and diastereoselectivity (≤10:1 dr), along with excellent enantioselectivity (typically >99% ee). The catalytic system performs efficiently at low catalyst loadings (1 mol %) and was tested with >50 examples, including some biologically active molecules.