Benzimidazol-Derivate und verwandte Heterocyclen V. Die Kondensation von o-Phenylendiamin mit aliphatischen und alicyclischen ?-Ketoestern
作者:A. Rossi、A. Hunger、J. Kebrle、K. Hoffmann
DOI:10.1002/hlca.19600430515
日期:——
The products of the condensation of o-phenylenediamine with ethyl acetoacetate were re-investigated. Depending on the reaction conditions, 2-methylbenzimidazole (II), 2-isopropenyl-benzimidazole-2-one (VI) and 4,7-dihydro-5-methyl-1H-2,3-benzo-1,4-diazepin-7-one (IV) were obtained. 2-Acetonylbenzimidazole, which had erroneously been described in the literature, could not be isolated from the above
重新研究了邻苯二胺与乙酰乙酸乙酯的缩合产物。根据反应条件,2-甲基苯并咪唑(II),2-异丙烯基-苯并咪唑-2-酮(VI)和4,7-二氢-5-甲基-1 H -2,3-苯并-1,4-二氮杂pine获得了-7-一(IV)。无法从上述反应中分离出文献中已被错误描述的2-乙酰基苯并咪唑。它是通过将邻苯二胺与乙酰乙酸乙酯的缩酮缩合,然后水解缩酮制备的。研究扩展到邻苯二胺与2-乙氧基环己酮和2-乙氧基环戊酮以及与N-取代的3-乙氧基-4-哌啶酮的反应。