Reaction of 4-Alkylaminodihydro-2(1H)-pyridinethions and -ones resp. with Bis-trichlorophenyl-ethylmalonate

Article abstract of DOI:10.1007/BF00800264

4-Alkylamino-2(1H)-pyridinethiones (1) react with bis-trichlorophenyl-ethylmalonate (3) to give four isomeric products: 5-thioxo-1,6-naphthyridine-2(1H)-ones (4), 7,7-dimethyl-4H-thiopyrano<2,3-b>pyridine-4-ones (6), 2,2-dimethyl-2H-thiopyrano<2,3-b>pyridine-5,7-dioles (7) and 2,2-dimethyl-2H-thiopyrano<2,3-b>pyridine-5(3H)-ones (8).On treatment with alkali the thioxogroup of 4 is hydrolyzed and 1,6-naphthyridinediones (5) are formed.Compound 5 can also be synthesized by heating the alkylaminopyridones (2) together with 3. 6 can be hydrolyzed to 2-thioxo-3-pyridylprop ylketones (12).On treatment with diluted alkali or conc. acid the aminogroup of 7 and 8 is hydrolyzed and 10 is formed.By heating in 20percent NaOH 10 is transformed to the dihydroxymercapto-3-pyridylmethylketone (11). - Keywords: 4-alkylaminodihydro-2(1H)pyridinthiones and -ones; Bis-trichlorphenylmalonate; 2H-Thiopyrano<2,3-b>pyridine-5,7-dioles; 4H-Thiopyrano<2,3-b>pyridine-4-ones; 2H-Thiopyrano<2,3-b>pyridine-5-ones; 5-Thioxo-1,6-naphthyridine-2(1H)-ones