Photochemical Asymmetric Nickel-Catalyzed Acyl Cross-Coupling

Angew Chem Int Ed Engl. 2019 Nov 18;58(47):16854-16858. doi: 10.1002/anie.201910168. Epub 2019 Oct 7.

Abstract

Photochemical enantioselective nickel-catalyzed cross-coupling reactions are difficult to implement. We report a visible-light-mediated strategy that successfully couples symmetrical anhydrides and 4-alkyl dihydropyridines (DHPs) to afford enantioenriched α-substituted ketones under mild conditions. The chemistry does not require exogenous photocatalysts. It is triggered by the direct excitation of DHPs, which act as a radical source and as a reductant, facilitating the turnover of the chiral catalytic nickel complex.

Keywords: asymmetric catalysis; cross-coupling; nickel catalysis; photochemistry; radical chemistry.