Asymmetric [3+2] cycloaddition of 3-amino oxindole-based azomethine ylides with α,β-ynones: a straightforward approach to spirooxindoles incorporating 2,5-dihydropyrroles and pyrroles

Abstract

An organocatalytic asymmetric [3+2] cycloaddition of 3-amino oxindole-based azomethine ylides and α,β-ynones has been developed. This reaction afforded spiro[dihydropyrrole-2,3′-oxindole] products in high chemical yields with excellent stereoselectivities (up to 99% yields, >20 : 1 dr and >99% ee). Notably, a series of important spiro[pyrrole-oxindole] derivatives were readily obtained via oxidation of the cycloadducts, thus extending the diversity of the products.