Asymmetric Photocatalytic C(sp3)-H Bond Addition to α-Substituted Acrylates

Asymmetric functionalization of inert C(sp(3))-H bonds is a straightforward approach to realize versatile bond-forming events, allowing the precise assembly of molecular complexity with minimal functional manipulations. Here, we describe an asymmetric photocatalytic C(sp(3))-H bond addition to alpha-substituted acrylates by using tetrabutylammonium decatungstate (TBADT) as a hydrogen atom transfer (HAT) photocatalyst and chiral phosphoric acid as a chiral proton-transfer shuttle. This protocol is supposed to occur via a radical/ionic relay process, including a TBADT-mediated HAT to cleave the inert C(sp(3))-H bond, a 1,4-radical addition, a back hydrogen abstraction, and an enantioselective protonation. A variety of inert C-H bond patterns and alpha-substituted acrylates are well tolerated to enable the rapid synthesis of enantioenriched astereogenic esters from simple raw materials.

Automated summary

The asymmetric functionalization of inert C(sp(3))-H bonds was achieved using a photocatalytic method with TBADT and chiral phosphoric acid, allowing rapid synthesis of enantioenriched astereogenic esters from simple raw materials.