[3+2] Cycloaddition of Nitrile Imines with 3‐Benzylidene Succinimides: A Facile Access to Functionalized Spiropyrazolines

A wide range of substituted spiro‐pyrazoline derivatives containing the pyrrolidinone core have been prepared by alkalic treatment of 3‐benzylidene succinimides and nitrile imines. All reactions proceeded under mild conditions and the products were isolated by column chromatography in good yields with high diastereoselectivity. Furthermore, this method featured several advantages such as good functional group tolerance and simple scalability.