Leveraging cascade annulation of 2-alkynylcyclopropanes with substituted azides to access fused N-heterocyclic scaffolds

Abstract

Herein, we present a substrate-dependent, efficient synthetic strategy for accessing two distinct N-heterocyclic frameworks, namely 1,6-naphthyridine and isochromeno[4,3-c]quinoline derivatives, from 2-alkynylcyclopropanes. Under identical reaction conditions, the reaction of 2-alkynylcyclopropane with either 2-azidobenzonitrile or 2-azidobenzaldehyde leads to divergent N-heterocycles. The reaction demonstrates a broad substrate scope, excellent functional group tolerance, high yields, and good scalability.