Li-Na Jia

A highly organocatalytic stereoselective double Michael reaction: efficient construction of optically enriched spirocyclic oxindoles

An effective double Michael reaction has been disclosed to access spirocyclic oxindoles in high yields (up to 98%) and excellent enantioselectivities (up to 98% ee).

Asymmetric Michael Addition of α-Substituted Isocyanoacetates with Maleimides Catalyzed by Chiral Tertiary Amine Thiourea

A highly diastereoselective and enantioselective Michael addition of α-substituted isocyanoacetates with maleimides catalyzed by bifunctional tertiary amine thioureas has been developed. Various chiral succinimide derivatives bearing adjacent quaternary and tertiary stereocenters were prepared in excellent yields (up to 98%), diastereoselectivities (up to 99:1), and enantioselectivities (up to 98% ee). The synthetic utility of chiral succinimide derivatives is also demonstrated in the preparation of h5-HT(1d) receptor agonist motifs.

Highly enantioselective aldol reaction of acetone with β,γ-unsaturated α-keto esters promoted by simple chiral primary–tertiary diamine catalysts

A series of primary-tertiary diamine catalysts were successfully applied to promote the enantioselective aldol reaction of acetone with β,γ-unsaturated α-keto esters in excellent yields (up to 99%) and enantioselectivities (up to 96% ee).

Highly enantioselective direct vinylogous Michael addition of γ-substituted deconjugated butenolides to maleimides catalyzed by chiral squaramides

Highly enantioselective direct vinylogous Michael reactions of γ-aryl-substituted deconjugated butenolides with maleimides, catalyzed by only 1 mol% bifunctional squaramides derived from cinchona alkaloids, were achieved with excellent yields (up to 96%) and enantioselectivities (up to 97% ee). This protocol features a very low catalyst loading, mild reaction conditions and provides a potential and effective method for the construction of optically active chiral butenolides with adjacent quaternary and tertiary stereocenters.