A Simple, Versatile Synthetic Route to<i>N</i>-1-Aryl-, -Heteroaryl-, - Acylmethyl-, -Carboxymethyl-and -Alkyl-benzotriazoles via Regiospecific or Highly Regioselective Substitutions of Benzotriazole
作者:Alan R. Katritzky、Jing Wu
DOI:10.1055/s-1994-25530
日期:——
In the absence of any added base in refluxing benzene or toluene, benzotriazole replaces the halogen atom of an α-halogenated ketone or a carboxylic ester to give the corresponding N-1-substituted benzotriazole as the only isomer. 2-Bromopyridine and 1-chloro-2,4-dinitrobenzene reacted similarly with benzotriazole to afford the corresponding N-1-substituted benzotriazole derivatives in quantitative yields. Alkyl halides reacted regioselectively to afford the N-1-alkylbenzotriazoles in ratios of more than 10 to 1 over the N-2 isomers. An α-(benzotriazol-1-yl)carboxylic ester was hydrolyzed into the corresponding carboxylic acid, which upon heating under-went smooth decarboxylation into the corresponding 1-alkylbenzotriazole.
在没有加入任何碱的回流苯或甲苯中,苯并三唑取代了α-卤代酮或羧酸酯中的卤原子,生成唯一的异构体,即相应的N-1-取代苯并三唑。2-溴吡啶和1-氯-2,4-二硝基苯与苯并三唑反应类似,以定量产率得到相应的N-1-取代苯并三唑衍生物。烷基卤化物反应时具有区域选择性,生成N-1-烷基苯并三唑的比率超过N-2异构体的10比1。一个α-(苯并三唑-1-基)羧酸酯被水解为相应的羧酸,在加热下经历平滑的脱羧反应,生成相应的1-烷基苯并三唑。