One-Pot Acid-Promoted Synthesis of 6-Aminopyrazolopyrimidines from 1<i>H</i>-Pyrazol-5-yl-<i>N</i>,<i>N</i>-dimethylformamidines or 5-Amino-1<i>H</i>-pyrazole-4-carbaldehydes with Cyanamide
作者:Ching-Chun Tseng、Shuo-En Tsai、Sin-Min Li、Fung Fuh Wong
DOI:10.1021/acs.joc.9b02653
日期:2019.12.20
acid-promoted synthesis of 6-aminopyrazolo[3,4-d]pyrimidine has been developed by treatment of 1H-pyrazol-5-yl-N,N-dimethylformamidines or 5-amino-1H-pyrazole-4-carbaldehydes with cyanamide (NH2C≡N) in an acid-mediated solution. This synthetic route involves four steps of deprotection, imination, the key acid-promoted heterocyclization, and aromatization. On the basis of optimized studies, methanesulfonylchloride
通过处理1H-吡唑-5-基-N,N-二甲基甲am或5-氨基-1H-吡唑,开发了一种方便高效的一锅酸促进6-氨基吡唑并[3,4-d]嘧啶的合成方法在酸介导的溶液中将-4-甲醛与氰胺(NH2CN)结合使用。该合成途径包括去保护,亚胺化,关键酸促进的杂环化和芳构化的四个步骤。在优化研究的基础上,甲磺酰氯被认为是最好的溶剂。此外,该方法还进行了微波辅助合成技术,以改进主要产物6-氨基吡唑并[3,4-d]嘧啶。此外,我们提出的机制在这项研究中得到证实,这表明N-[(5-氨基-1,3-二芳基-1H-吡唑-4-基)亚甲基]氰酰胺是中间体。