Cobalt-Catalyzed Asymmetric Hydroboration of Alkenyl Acetals

Transition-metal-catalyzed asymmetric hydroboration of alkenes has emerged as a powerful tool for constructing chiral boronates, yet asymmetric hydroboration of functionalized alkenes remains underdeveloped. Herein, we report a cobalt-catalyzed asymmetric hydroboration of alkenyl acetals, enabling efficient access to enantioenriched boryl acetals (up to 99% ee). The reaction proceeds efficiently on a gram scale with only 1 mol % catalyst and enables diverse downstream functionalizations, highlighting the synthetic potential of the resulting boryl acetals.