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Updated: May 14, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Catalytic asymmetric [4 + 2] cycloadditions and Hosomi-Sakurai reactions of α-alkylidene β-keto imides
Kohei Orimoto1, Harufumi Oyama, Yuki Namera
1Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan.
Abstract:
Highly enantioselective catalytic asymmetric reactions of rationally designed α-alkylidene β-keto imides are described. The [4 + 2] cycloadditions and Hosomi-Sakurai reactions of α-alkylidene β-keto imides proceed with high enantioselectivity and yield. The [4 + 2] cycloadditions of the imides with various dienes afford products bearing an all-carbon quaternary stereogenic center at the ring junction. α-Alkylidene β-keto imides should be useful for the enantioselective total synthesis of natural products and other catalytic asymmetric applications.
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