A novel annelation to quinolines and isoquinolines under Friedel–Crafts conditions: a one-step synthesis of functionalized pyridoquinolines and pyridoisoquinolines
Oxokohlenstoffe und verwandte Verbindungen;18. Mitteilung<sup>1</sup>. Umsetzung von Perchlorcyclobutenon mit Pyridinen: Synthese von 4<i>H</i>-4-Chinolizinonen im Eintopfverfahren
作者:Arthur H. Schmidt、Mario Dümmler
DOI:10.1055/s-1992-26281
日期:——
Oxocarbons and Related Compounds; Part 18.1 The Reaction of Perchlorocyclobutenone with Pyridines: A Novel Synthesis of 4H-4-Quinolizinones Heating of tetrachlorocyclobutenone (5) with the pyridines 6a-i followed by treatment with water affords 1,3-dichloro-2-hydroxy-4H-4-quinolizinones 7a, b, g-h and 1,3-dichloro-2-hydroxy-4-oxo-4H-quinolizinecarboxylates 7c-f. The reaction pathway has been secured by trapping 1,2,3-trichloro-8-(1,1-dimethylethyl)-4H-4-quinolizinone (11b) and by its successive conversion to 7b on heating with water.