Synthesis of Quinoline and 1,2,3,4‐Tetrahydroquinoline Derivatives from Substituted o‐Nitrotoluenes via Cesium‐promoted [2 + 4] Cycloaddition

An atom economical highly efficient method has been developed for the synthesis of quinoline and 1,2,3,4-tetrahydroquinoline derivatives from o-nitrotoluenes bearing electron-withdrawing groups and olefins (acrylic esters, acrylonitriles, and methyl acrylates) via a base-catalyzed [2 + 4] cycloaddition. This simple, rapid, and environment- friendly method provides a practical pathway for the synthesis of quinoline and 1,2,3,4-tetrahydroquinoline derivatives. The starting materials are readily available and 37 products were obtained in good to excellent yields.