Bis(oxazoline)–Nickel(II)‐Catalyzed Asymmetric Photochemical Hydroxylation of β‐Keto Esters With Nitrones

Nitrones have been extensively employed as electrophiles, 1,3‐dipoles, and radical acceptors in organic chemistry. In contrast, their photochemical transformations, especially in the context of asymmetric catalysis, have remained elusive. Herein we disclose the first enantioselective phototransformation of nitrones for the hydroxylation of β‐keto esters under bis(oxazoline)–Ni(II) catalysis. This photocatalyst‐free method affords chiral α‐hydroxy β‐keto esters in high yields and excellent enantioselectivity (up to 94% yield, 93% ee). This work opens new chemical space for asymmetric photochemistry of nitrones.