Condensation of Schiff bases of o-hydroxyarenecarboxaldehydes with 3-arylpentenedioic or homophthalic acid anhydrides was found to give 1,4,6-triaryl-5-carboxy-2-oxo-1,2-dihydropyridines and 2,3-Diaryl-4-carboxy-1-oxo-1,2-dihydroisoquinolines, respectively, instead of the expected tetrahydro products. The Schiff bases (used in excess) oxidize the intermediate tetrahydro products to the title compounds.
研究发现,邻羟基
壬醛的席夫碱与 3-芳基
戊烯二酸或均苯二
甲酸酸酐缩合后,会分别生成 1,4,6-三芳基-5-羧基-2-氧代-1,2-
二氢吡啶和 2,3-二芳基-4-羧基-1-氧代-1,2-二氢
异喹啉,而不是预期的四氢产物。希夫碱(过量使用)将中间四氢产物氧化成标题化合物。