Synthesis of polynuclear heterocycles. Part II. Cyclisations of 2- and 4-substituted 3-amino- and 3-nitro-pyridines
作者:J. J. Eatough、L. S. Fuller、R. H. Good、R. K. Smalley
DOI:10.1039/j39700001874
日期:——
Treatment of 2- and 4-phenoxy-3-nitropyridine with triethyl phosphite failed to yield the expected pyridobenz-oxazines; 2- and 4-phenylthio-3-nitropyridine, however, cyclised to give 5H-pyrido [2,3-b][1,4] benzothiazine and 5H-pyrido[3,4-b][1,4]benzothiazine respectively, albeit in poor yield. Similar results were obtained by thermolytic decomposition of the corresponding 2- and 4-substituted 3-azido-pyridines
用亚磷酸三乙酯处理2-和4-苯氧基-3-硝基吡啶不能得到预期的吡啶并恶唑。然而,将2-和4-苯硫基-3-硝基吡啶环化,得到5 H-吡啶[2,3- b ] [1,4]苯并噻嗪和5 H-吡啶[3,4- b ] [1,4]苯并噻嗪虽然收率差。通过相应的2-和4-取代的3-叠氮基吡啶的热解分解获得相似的结果。已经合成了9-羟基吡啶并[2,3- b ] 1,4,5-苯并二氮杂卓。