Atroposelective Synthesis of Axially Chiral Styrenes by Dual Photoredox/Copper-Catalyzed Carbocyanation of Alkynes

The atroposelective synthesis of axially chiral styrenes remains a formidable challenge due to the configurational lability and the difficulty in controlling alkene geometry. Herein, we report a synergistic photoredox/copper-catalyzed carbocyanation of terminal alkynes that enables efficient access to these valuable scaffolds. Under redox-neutral conditions, a wide range of readily available N-hydroxyphthalimide esters and 2-aminoaryl alkynes are efficiently converted into the corresponding styrene atropisomers in good yields with high enantioselectivity and E-selectivity. The practicality of this method is highlighted by successful scale-up reactions and versatile downstream transformations, providing a general and efficient strategy for synthesizing configurationally unstable axially chiral alkenes.