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Updated: May 23, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Au-catalyzed asymmetric formal [3 + 2] cycloaddition of isocyanoacetates with maleimides
Silvia Padilla1, Javier Adrio, Juan C Carretero
1Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Abstract:
An efficient protocol for the Au(I)-catalyzed asymmetric formal [3 + 2] cycloaddition of isocyanoacetates with phenylmaleimide has been developed. In the presence of cationic Au(I)/DTBM-segphos complex, excellent diastereoselectivity and high levels of enantioselectivity (up to 97% ee) have been attained with a variety of α-substituted isocyanoacetates. The synthetic potential of the resulting enantioenriched 1-pyrrolines has been demonstrated by the preparation of highly substituted pyrrolidines bearing a quaternary stereocenter.
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