Institute of Organic Chemistry, Clausthal University of Technology, Leibnizstr. 6, 38678 Clausthal-Zellerfeld, Germany.
Beilstein J Org Chem. 2012;8:621-8. doi: 10.3762/bjoc.8.69. Epub 2012 Apr 23.
The nitropolychlorobutadienes 3, 4 are valuable building blocks for various amination and successive heterocyclization products. Nucleophilic substitution reactions of the partially protected, bioactive amines 1, 2 with either vinyl, imidoyl or carbonyl chlorides result in the formation of the enamines 11, 12, 13, 16, 25, the amidine 6, and the amides 20, 21, respectively. In the following, cyclization to the highly functionalized pyrazoles 27, 28, pyrimidine 26 and pyridopyrimidine 24 succeeded. Deprotection of 21, 12 and 28 proved to be only partially feasible.
硝基亚甲基氯丁二烯 3、4 是各种胺化和连续杂环化产物的有价值的构建块。部分保护的生物活性胺 1、2 与乙烯基、亚胺基或羰基氯的亲核取代反应分别生成烯胺 11、12、13、16、25、脒 6 和酰胺 20、21。在接下来的反应中,高度官能化的吡唑 27、28、嘧啶 26 和吡啶并嘧啶 24 顺利地环化。21、12 和 28 的脱保护证明只有部分可行。