Selective Cyanation of Benzylic C(sp³)–H Bonds Using Photoelectrochemical Asymmetric Catalysis

Key words

copper catalysis - enantioselectivity - photoelectrochemistry

Significance

In this report, photoelectrochemistry is paired with asymmetric catalysis for the site- and enantioselective cyanation of benzylic C(sp³)–H bonds. Mechanistic experiments were used to elucidate the reaction pathway, in which the authors propose the benzylic C(sp³)–H cleavage to proceed through two tandem catalytic cycles: a photocatalyzed electron transfer and a subsequent copper-catalyzed asymmetric C–C bond formation.

Comment

The reaction was compatible with various functionalized alkylbenzenes, including electron-rich and electron-deficient substrates. Notably, for systems bearing multiple potential sites for cyanation, functionalization occurs in a predictable and selective fashion at the most electron-rich site or sterically accessible benzylic C–H bond.

Publication History

Article published online:
16 December 2022