Catalysis

Enantioselective synthesis

Reaction mechanism

Transition state

Lewis acids and bases

Lewis acid catalysis

Combinatorial chemistry

Cyclohexene

Organic chemistry

Epoxide

Catalytic cycle

Stereoselectivity

Chemistry

Angewandte Chemie International Edition

The first catalytic asymmetric multiple vinylogous addition reactions initiated by Meinwald rearrangement of vinyl epoxides were realized by employing chiral N , N ′‐dioxide/Sc III complex catalysts. The vinyl epoxides, as masked β,γ‐unsaturated aldehydes, via direct vinylogous additions with isatins, 2‐alkenoylpyridines or methyleneindolinones, provided a facile and efficient way for the synthesis of chiral 3‐hydroxy‐3‐substituted oxindoles, α,β‐unsaturated aldehydes and spiro‐cyclohexene indolinones, respectively with high efficiency and stereoselectivity. The control experiments and kinetic studies revealed that the Lewis acid acted as dual‐tasking catalyst, controlling the initial rearrangement to match subsequent enantioselective vinylogous addition reactions. A catalytic cycle with a possible transition model was proposed to illustrate the reaction mechanism.

Asymmetric Catalytic Vinylogous Addition Reactions Initiated by Meinwald Rearrangement of Vinyl Epoxides