Metal‐to‐Ligand Ratio‐Dependent Chemodivergent Asymmetric Synthesis

Abstract

Chemodivergent asymmetric synthesis was achieved by tuning the metal‐to‐ligand ratio in an organometallic catalytic system. Using N‐(aroyloxy)phthalimide as the precursor of either an oxygen‐centered aroyloxy radical or a nitrogen‐centered phthalimidyl radical, enantioselective oxocyanation or aminocyanation of alkenes was achieved separately through a dual photoredox and copper catalysis. The metal‐to‐ligand ratio can exert chemoselective control while retaining the high enantiopurity of divergent products. Both reactions proceed efficiently with catalyst loading as low as 0.2 mol % and can be performed on a gram scale without loss of chemoselectivity or enantioselectivity. Chemodivergent asymmetric 1,5‐aminocyanation or 1,5‐oxocyanation of vinylcyclopropane can also be realized by this protocol. Mechanistic investigations involving electron paramagnetic resonance (EPR) experiments were performed to shed light on the stereochemical and chemodivergent results.