with ethyl (triphenylphosphoranylidene)acetate leads to 5,6-dihydro-2H-pyrano[3,2-c]quinoline-2,5-diones (2), which were brominated to 3-bromo derivatives (4). Alkaline hydrolysis of 4 gives 2-alkyl/aryl-4-oxo-4,5-dihydrofuro[3,2-c]quinoline-3-carboxylic acids (6), which were decarboxylated to 2-alkyl/aryl-5H-furo[3,2-c]quinolin-4-ones (8). The reaction of 3-acetyl-4-hydroxy-1-methyl-1H-quinolin-2-one
用 (三苯基正膦亚基)
乙酸乙酯处理 3-acyl-4-hydroxy-1H-quinolin-2-ones (1) 得到 5,6-dihydro-2H-pyrano[3,2-c]quinoline-2,5 -二酮 (2),其被
溴化为 3-
溴衍
生物 (4)。4 的碱性
水解得到 2-烷基/芳基-4-氧代-4,5-二氢
呋喃[3,2-c]
喹啉-3-羧酸 (6),将其脱羧为 2-烷基/芳基-5H-
呋喃[3,2-c]quinolin-4-ones (8)。3-乙酰基-
4-羟基-1-甲基-1H-
喹啉-2-酮(Ia)与
氯代
乙酸乙酯(三苯基正膦亚基)的反应不仅在乙酰基上进行,而且在酰胺基上也进行,得到乙基3的混合物,5-dimethyl-4-oxo-4,5-dihydrofuro[3,2-c]quinoline-2-carboxylate (11a) 和 4,6-dimethyl-2-oxo-5,6-dihydro-2H-pyrano