Catalytic asymmetric construction of dispirotriheterocyclic structures through [3+2] cycloadditions of 4-amino pyrazolone-based azomethine ylides

Abstract

An efficient and convenient catalytic asymmetric [3+2] cycloaddition of 4-amino pyrazolone-based azomethine ylides with methyleneindolinones was developed. This protocol leads to the construction of dispiro[pyrazolone–pyrrolidine–oxindole] scaffolds bearing four contiguous stereogenic centers, including two spirocenters in high yields with excellent stereoselectivities (up to 98% yields, >20 : 1 dr and >99% ee) under mild conditions.