Catalyst-Free Synthesis of Pyrrolo[1,2‑a]quinolines via Dehydration/[3 + 2] Cycloaddition Directly from 2‑Methylquinolines, Aldehydes, and Alkynoates

A simple and efficient catalyst-free synthesis of pyrrolo­[1,2-a]­quinoline derivatives from 2-methylquinolines, aldehydes, and alkynoates via dehydration/[3 + 2] cycloaddition has been developed. The reaction conditions are tolerant to air, and H2O is the only byproduct of this transformation, thus offering an environmentally benign process with a wide range of potential applications in organic synthesis and medicinal chemistry.