Studies in the Synthesis of Quinoline Derivatives: Part VI. Synthesis of Pyranoquinolines and Quinolinolactones

Chemistry Department, Faculty of Science, M. S. University of Baroda, Baroda. Received August 11, 1971 5-Methyl- and 5,7-dimethyl-2-oxo-2H-pyrano (3, 2-c) quinoline and their 3-phenyl derivatives were prepared from 2-methyl- and 2, 8-dimethyl-3-formyl-4-hydroxyquinoline respectively by Perkin reaction. Several substituted acetoacetarylamides were condensed with ethyl bromoacetate to give α-carboethoxyrnethylacetoacetarylanlides and cyclised with cone. sulphuric acid to 4-methyl-2-hydroxyquinoline-3-acetic acid derivatives. These on treatment with acetic anhydride gave quinoline-lactone derivatives. Similar condensation on ethyl bromo propionate gave 4-methyl-, 4, 6-dimethyl- and 4,8-dimethyl-2-hydroxyquinoline-3-propionic acid derivatives