Enantioselective Mannich reactions of pyruvates catalyzed by amine-based catalyst systems, in which pyruvates act as nucleophiles, are reported. The reactions of pyruvates and cyclic sulfonylimines afforded the desired Mannich products, including those bearing tetrasubstituted carbon centers, in high yields with high enantioselectivities in most cases. The selection of the acid used in the amine-based catalyst system was key for the formation of the Mannich products with high enantioselectivities.

An efficient g-epimerization of g-vinyl-g-butyrolactone is studied under palladium catalysis. The building blocks derived there in are used in an efficient stereoselective synthesis of (+)-exo-and (+)-endobrevicomins.

Direct asymmetric synthesis of δ-hydroxy-β-ketoesters was accomplished via regio- and enantioselective aldol reactions of β-ketoesters with isatins catalyzed by cinchona alkaloid thiourea derivatives. The C–C bond formation of the reactions occurred only at the γ-position of the β-ketoesters. Reaction progress monitoring and product stability analyses under the conditions that included the catalyst indicated that the γ-position reaction products were formed kinetically. Various δ-hydroxy-β-ketoesters bearing 3-alkyl-3-hydroxyoxindole cores relevant to the development of bioactive molecules were synthesized.

A domino palladium‐catalyzed recombinant γ‐isomerization and reverse Wacker oxidation of γ‐vinyl‐γ‐butyrolactone has been explored. The strategy has been used in the stereoselective synthesis of (+)‐trans‐, (–)‐ and (+)‐disparlures. The synthesis was achieved in seven to eight steps from D‐glucono‐δ‐lactone with overall yields of 19.3, 20.7 and 22.6 %, respectively.

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