Preparation and Reaction of 3-Oxo-3H-pyrazolo(1,5-a)indole Derivatives.
作者:Jing-Kang SHEN、Hajime KATAYAMA
DOI:10.1248/cpb.42.222
日期:——
An alternative method to prepare 3-oxo-2-phenyl-3H-pyrazolo[1, 5-a]indoles starting from indoline-2-carboxylic acid was explored. The reaction with nucleophilic agents allowed us to introduce the properly substituted alkyl substituents at C-4 of the 4H-pyrazolo[1, 5-a]indoles. The 2, 3-dichloro-5, 6-dicyano-p-benzoquinone (DDQ) oxidation of these products gave the 3-oxo-2-phenyl-3H-pyrazolo[1, 5-a]indole derivatives. Selective Keto-enol tautomerizations of these 1, 5-diketo-monoene system were observed.
探索了从吲哚啉-2-羧酸出发制备3-氧代-2-苯基-3H-[1,5-a]吡唑并[1,5-a]吲哚的替代方法。通过与亲核试剂反应,我们能够在4H-[1,5-a]吡唑并[1,5-a]吲哚的C-4位引入适当取代的烷基取代基。这些产物经2,3-二氯-5,6-二氰基对苯醌(DDQ)氧化后,得到了3-氧代-2-苯基-3H-[1,5-a]吡唑并[1,5-a]吲哚衍生物。观察到这些1,5-二酮单烯体系的选择性酮式-烯醇式互变异构现象。