Fig. 1: Catalytic oxidation of internal alkenes to ketones.

a, Regioselectivity is a challenge in the catalytic oxidation of internal alkenes to ketones. b, Design of a catalytic process to convert internal alkenes into ketones using high-valent metal–oxo species as the catalytic oxidant. High-valent metal–oxo species typically react with alkenes in epoxidation reactions. The ketone product is accessible by stabilizing a carbocation intermediate, and the reaction proceeds via a coupled electron–hydride transfer. c, Given that enzymatic alkene to ketone oxidation can be accessed, many challenging functionalization reactions of internal alkenes can be realized in combination with established biocatalysts such as ketoreductases^39,40 (i), ω-transaminases³⁹ (ii) and imine reductases^41,42 (iii).