Nickel-Catalyzed Three-Component Alkylacylation of Alkenes Enabled by a Photoactive Electron Donor–Acceptor Complex

Abstract

An electron donor–acceptor complex-enabled, nickel-catalyzed three-component net-reductive 1,2-alkylacylation of alkenes is developed. This conjunctive reductive acyl cross-coupling process obviates the use of an exogenous photocatalyst and a stoichiometric metal-based reductant, affording various synthetically useful 1,3-dicarbonyl compounds in good yields with a broad substrate scope and excellent functional group tolerance. Both alkyl and acyl electrophiles are derived from the highly abundant and readily accessible carboxylic acids, making the catalytic 1,2-dicarbofunctionalization more synthetically general and sustainable.

Radical acylation: concepts, synthetic applications and directions

“…Importantly, a wide range of alkanes with different kinds of functional groups were successfully employed as radical precursors, thus delivering the corresponding functionalized ketones with satisfactory yields and excellent regioselectivities. Concurrent with Ackermann's initial discovery that outlined the metallaphotoredox carboacylation of electron-deficient alkenes, Yuan and co-workers disclosed the electron donor–acceptor complex-enabled, nickel-catalyzed carboacylation of electron-deficient alkenes, 104 which takes the 2-pyridyl esters as acyl donors and NHPI esters as alkyl radical precursors and circumvents the use of the exogenous photocatalyst and stoichiometric metal reductants.…”

Recent Advances in Nonprecious Metal Catalysis

“…In another report of 1,2-dicarbofunctionalization of olefins, Yuan and co-workers described 1,2-alkylacylation of alkenes affording synthetically useful 1,3-dicarbonyl compounds in good yields with excellent functional group tolerance (Scheme 21). 42 Several advances have been made in the area of 1,2dicarbofunctionalization of olefins using synergistic photoredox/nickel catalysis; however, most reports are restricted to organohalides as coupling partners. The current work uses carboxylic acid esters as the coupling partners.…”

Photocatalyst-free, metal-free, visible light-induced thiolation/pyridylation of styrenes using an electron donor–acceptor complex as a bifunctional reagent

“…To date, only a few examples of intermolecular three-component difunctionalization of alkenes using methods based on EDA complexes have been documented. 4 Usually, these methods need redox auxiliaries to modulate the substrate and sacrificial donor ( e.g. , Hantzsch ester), which reduces the atom economy of these reactions (Fig.…”