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Asymmetric functionalization of inert C(sp3)–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(sp3)–H bond addition to α-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(sp3)–H bond, a 1,4-radical addition, a back hydrogen abstraction, and an enantioselective protonation. A variety of inert C–H bond patterns and α-substituted acrylates are well tolerated to enable the rapid synthesis of enantioenriched α-stereogenic esters from simple raw materials.

Asymmetric functionalization of the C(sp3)–H bond is an attractive yet challenging strategy to achieve versatile bond-forming events, enabling the precise assembly of molecular complexity with minimal manipulation of functional groups. Here, we report an asymmetric C(sp3)–H/C(sp3)–H umpolung coupling of N-allylimine and coordinating α-aryl carbonyls by using chiral phosphoramidite-palladium catalysis. A wide variety of α-heteroaryl ketones and 2-acylimidazoles are nicely tolerated to open a convenient and tunable avenue for efficient synthesis of enantioenriched β-amino-γ,δ-unsaturated carbonyl derivatives with high levels of regio- and stereoselectivities, capable of providing a key intermediate for asymmetric synthesis of Focalin. This protocol showcases an umpolung reactivity of the N-allylimines through a concerted proton and two-electron transfer process to cleave the allylic C–H bond, effectively complementing established methodology for allylic C–H functionalization. An inner-sphere allylation pathway for both α-heteroaryl carbonyls and 2-acylimidazoles to attack the π-allylpalladium species is suggested by computational studies and experimental facts, wherein the nitrogen coordination to the palladium center enables the preference of branched regioselectivity.