An efficient solution phase synthesis of triazadibenzoazulenones: 'designer isonitrile free' methodology enabled by microwaves
An efficient solution phase synthesis of triazadibenzoazulenones: 'designer isonitrile free' methodology enabled by microwaves
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DOI：
10.1016/j.tetlet.2009.02.099
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发表时间：
2009-04-29
影响因子：
1.8
通讯作者：
Dietrich, Justin
中科院分区：
文献类型：
--
作者：
Hulme, Christopher;Chappeta, Shashi;Dietrich, Justin
报道了一种新的两步液相法合成三氮杂二苯并唑烯酮阵列的方法。该方法采用Ugi反应来组装所需的多样性，酸处理可以实现两个串联环闭合转化。闭合环的顺序是最佳转化为期望的四环产物的关键，最初通过苯并咪唑中间体进行，然后第二个闭合环得到期望的融合苯二氮卓。微波辐照进一步促进了两步方案。谨慎选择异腈试剂可以使环形成事件的正确顺序。因此，该方法代表了采用两种内部氨基亲核试剂的冷凝后Ugi修饰的第一个例子。2009爱思唯尔有限公司版权所有。
A novel two-step solution phase protocol for the synthesis of arrays of triazadibenzoazulenones is reported. The methodology employs the Ugi reaction to assemble desired diversity and acid treatment enables two tandem ring closing transformations. The order of ring closure is shown to be key for optimal conversion to the desired tetra-cyclic product and initially proceeds through a benzimidazole intermediate, followed by second ring closure to give the desired fused benzodiazepine. The two-step protocol is further facilitated by microwave irradiation. Prudent selection of the isonitrile reagent enables the correct order of ring forming events. As such the methodology represents the first example of a post-condensation Ugi modification that employs two internal amino nucleophiles. (C) 2009 Elsevier Ltd. All rights reserved.