The asymmetric allylic alkylation (AAA), which features employing active allylic substrates, has historical significance in organic synthesis. The allylic C−H alkylation is principally more atom-and step-economic than the classical allylic functionalizations and thus can be considered a transformative variant. However, asymmetric allylic C−H alkylation reactions are still scarce and yet underdeveloped. Herein, we have found that Z/E-and regioselectivities in the Pd-catalyzed asymmetric allylic C−H alkylation of 1,4-dienes are highly dependent on the type of nucleophiles. A highly stereoselective allylic C−H alkylation of 1,4-dienes with azlactones has been established by palladium-chiral phosphoramidite catalysis. The protocol proceeds under mild conditions and can accommodate a wide scope of substrates, delivering structurally divergent α,αdisubstituted α-amino acid surrogates in high yields and excellent levels of diastereo-, Z/E-, regio-, and enantioselectivities. Notably, this method provides key chiral intermediates for an efficient synthesis of lepadiformine marine alkaloids. Experimental and computational studies on the reaction mechanism suggest a novel concerted proton and two-electron transfer process for the allylic C−H cleavage and reveal that the Z/E-and regioselectivities are governed by the geometry and coordination pattern of nucleophiles.

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In the presence of tetrabutylammonium decatungstate and chiral spiro phosphoric acid, a light-mediated asymmetric C–H functionalization of unactivated hydrocarbons with exocyclic enones has been established. A wide range of cycloalkanes, benzylic, and allylic hydrocarbons are tolerated. This protocol proceeds via a hydrogen atom transfer/radical addition/hydrogen abstraction/enantioselective protonation relay process.

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.