Intramolecular cyclization of O-(3,5-dinitrophenyl) and O-(3-amino-5-nitrophenyl) ketoximes, products of transformations of 1,3,5-trinitrobenzene. The synthesis of nitrobenzo[b]furans and 4-hydroxynitroindoles
作者:S. S. Vorob’ev、M. D. Dutov、I. A. Vatsadze、E. P. Petrosyan、V. V. Kachala、Yu. A. Strelenko、S. A. Shevelev
DOI:10.1007/s11172-007-0153-6
日期:2007.5
O-(3,5-Dinitrophenyl) ketoximes obtained in the reactions of ketoximes with 1,3,5-trinitrobenzene undergo acid-catalyzed cyclization into 2-substituted or 2,3-disubstituted 4,6-dinitrobenzo[b]furans. In analogous cyclization, products of selective reduction of a nitro group in O-(3,5-dinitrophenyl) ketoximes unexpectedly yield, along with 6-amino-4-nitrobenzofurans, 4-hydroxy-6-nitroindoles. The 4-NO2 group is displaced from 4,6-dinitrobenzo[b]furans in reactions with thiols in the presence of K2CO3. Conditions for nitration and sulfochlorination of 4,6-dinitrobenzo[b]furans in position 3 were found. Condensation of a 2-methyl derivative with dimethylformamide acetal was accomplished.
在酮肟与 1,3,5-三硝基苯反应中得到的 O-(3,5-二硝基苯基)酮肟在酸催化下环化成 2-取代或 2,3-二取代的 4,6-二硝基苯并[b]呋喃。在类似的环化过程中,选择性还原 O-(3,5-二硝基苯基)酮肟中的硝基的产物意外地与 6-氨基-4-硝基苯并呋喃一起生成了 4-羟基-6-硝基吲哚。在 K2CO3 的存在下,4,6-二硝基苯并[b]呋喃中的 4-NO2 基团与硫醇发生反应而发生位移。找到了 4,6-二硝基苯并[b]呋喃第 3 位硝化和磺酰氯化的条件。完成了 2-甲基衍生物与二甲基甲酰胺缩醛的缩合。