AN IMPROVED SYNTHESIS OF 2,2-DISUBSTITUTED-1,2-DIHYDROQUINOLINES AND THEIR CONVERSION TO 3-CHLORO-2,2-DISUBSTITUTED-TETRAHYDROQUINOLINES

摘要

N-(1,1-disubstitutedpropargyl)anilines can be cyclised to 2,2-disubstituted-12-dihydroquinolines by refluxing them in toluene containing cuprous chloride. Electron donating groups in the para position of the ring enhance the reaction rare and electron withdrawing groups markedly decrease the rare. The derived N-acetyldihydroquinolines can be cis dichlorinated and selectively monodechlorinated at the benzylic position to produce 3-chlorotetrahydroquinolines. [References: 9]