Regioselectivity in the Reaction of 2‐Aminobenzothiazoles and 2‐Aminobenzimidazoles with Enaminonitriles and Enaminones: Synthesis of Functionally Substituted Pyrimido[2,1‐<i>b</i>][1,3]benzothiazole and Pyrimido[1,2‐<i>a</i>]benzimidazole Derivatives
作者:Abdulaziz Alnajjar、Mervat Mohammed Abdelkhalik、Hossam Mohammed Riad、Samia Mohammed Sayed、Kamal Usef Sadek
DOI:10.1002/jhet.3337
日期:2018.12
A variety of new polyfunctionally substituted benzo[d]pyrimido[2,1‐b][1,3]thiazole and benzo[4,5]imidazo[1,2‐a]pyrimidine derivatives have been synthesized. The general synthetic procedure used for this purpose involves the condensation of 2‐aminobenzothiazole and 2‐aminobenzimidazole with a variety of enaminonitriles, enaminones, and acrylaldehyde. The regioselectivity for initial attack of either
各种新的多官能取代的苯并[ d ]嘧啶基[2,1– b ] [1,3]噻唑和苯并[4,5]咪唑[1,2- a ]已经合成了]嘧啶衍生物。用于该目的的一般合成方法涉及2-氨基苯并噻唑和2-氨基苯并咪唑与各种烯氨基腈,烯胺和丙烯醛的缩合。研究并合理化了对环内环氮或环外氨基的初始进攻的区域选择性。可以得出结论,环氮是酸性介质中反应性最强的分子,也可以分离出环状中间体,这证明了环化后的结论。然而,在碱性或中性介质中,发现环外氨基是反应性最高的中心。尽可能通过元素分析,光谱数据和替代合成路线阐明了新合成化合物的所有结构。