Visible light photoredox-catalyzed difunctionalization of electron-deficient alkenes with tert-butyl nitrite: oxocarboxylic acid as an acyl source.

We report a visible-light photoredox-catalyzed acylative oximation of electron-deficient alkenes using tert-butyl nitrite and α-oxocarboxylic acids, providing direct access to β-keto oxime derivatives under mild conditions. The protocol combines tert-butyl nitrite as an NO donorwith acyl radicals generated through photoredox-mediated decarboxylation of α-oxocarboxylic acids. Vinyl sulfones and several other activated alkenes undergo the transforamtion to afford the corresponding products in moderate yields. Preliminary mechanistic studies support the involvement of acyl radical intermediates. The transformation can also be implemented under continuous photoflow conditions, demonstrating the operational adaptability of the protocol.