上海科技大学知识管理系统

Transition metal-catalyzed asymmetric allylic substitution with a suitably pre-stored leaving
group in the substrate is widely used in organic synthesis. In contrast, the enantioselective
allylic C(sp3)-H functionalization is more straightforward but far less explored. Here we
report a catalytic protocol for the long-standing challenging enantioselective allylic C(sp3)-H
functionalization. Through palladium hydride-catalyzed chain-walking and allylic substitution,
allylic C-H functionalization of a wide range of acyclic nonconjugated dienes is achieved in
high yields (up to 93% yield), high enantioselectivities (up to 98:2 er), and with 100% atom
efficiency. Exploring the reactivity of substrates with varying pKa values uncovers a reasonable
scope of nucleophiles and potential factors controlling the reaction. A set of efficient
downstream transformations to enantiopure skeletons showcase the practical value of the
methodology. Mechanistic experiments corroborate the PdH-catalyzed asymmetric migratory
allylic substitution process.