An efficient DMAP-catalyzed [4 + 3] annulation of ninhydrin-derived MBH carbonates with acyclic azadienes was developed, providing a series of polysubstituted, pharmacologically interesting spiro[indanone-azepine] derivatives in good to excellent yields (up to 98%) under mild conditions. The successful scale-up reaction and further derivatization of the product demonstrate the practicality and reliability of this method.

Abstract

Indanedione-containing spirocyclic derivatives are of significant interest in medicinal chemistry. However, spirofusion of indanediones with seven-membered rings remains relatively unexplored. In this study, we report an efficient DMAP-catalyzed [4 + 3] annulation of ninhydrin-derived MBH carbonates with acyclic azadienes, providing a series of polysubstituted, pharmacologically interesting spiro[indanone-azepine] derivatives in good to excellent yields (up to 98%) under mild conditons. The method is practical, tolerant of various functional groups, and allows for the rapid synthesis of a diverse range of products from simple, readily available starting materials. The successful scale-up reaction and derivatization of the product further demonstrate the practicality and reliability of this method.