作者:Qi Guo、Mingshuo Xu、Shuang Guo、Fuqiang Zhu、Yuanchao Xie、Jingshan Shen
DOI:10.1007/s11696-018-0654-9
日期:2019.5
bromination, Pd-catalyzed cyanation, and Sandmeyer diazotization/chlorination. This protocol eliminated the hazardous POCl3 of previous synthetic methods and offered a better yield (48%) which was 1.3-fold higher than a recently published procedure. From intermediate 8, the subsequent nucleophilic fluorination, nitrile hydration and hydroxyl substitution efficiently afforded the target product. Another
首先从廉价的和可商购的起始原料2-氨基吡嗪合成法维拉韦。方案4中嵌入的优选路线由七个步骤组成,并且通过3,6-二氯吡嗪-2-甲腈8的新颖而有效的合成得到了强调。在四个连续步骤中制备该中间体,所述四个步骤为吡嗪环的区域选择性氯化,溴化,Pd催化的氰化和Sandmeyer重氮化/氯化。该方案消除了先前合成方法中的有害POCl 3并提供了更高的收率(48%),比最近公布的方法高1.3倍。从中间8然后,随后的亲核氟化,腈水合和羟基取代有效地提供了目标产物。还研究了另一种使用相同原料的合成方法,以绕过引起过敏的二氯中间体8。但是,未实现中间体19或22在吡嗪C6位置进行单氟化的关键步骤。