切换N-基化TrifluoromethylatedPyrazoles的区域选择性由功能组调指导
Yulia O Edilova1, Yulia S Kudyakova1, Ekaterina A Osipova1,2
1Postovsky Institute of Organic Synthesis, Ural Branch of the Russian Academy of Sciences, Yekaterinburg 620137, Russia.
由于类似的原子特性,控制醇中的N功能化具有挑战性. 这项研究表明,松替代剂如何在三甲基醇中直接化选择性.
科学领域:
- 有机化学 有机化学
- 异环化学 异环化学
背景情况:
- 亚环,特别是醇,在区域选择性N-功能化方面存在挑战,因为它们的原子具有相似的化学性质.
- 控制pyrazole环上的化部位对于合成具有所需性质的特定衍生物至关重要.
研究的目的:
- 调查水替代剂对三甲基醇中N-化区域选择性的影响.
- 开发用于合成特定的3-和5-三甲基 (trifluoromethyl) 醇区域异构体的反应条件.
- 隔离和描述在bis-pyrazolyl NH-ketazine的化过程中形成的所有区域异构体.
主要方法:
- 合成3和5三甲基 (trifluoromethyl) 皮拉.
- 对bis-pyrazolyl NH-ketazine 的化反应.
- 区域异构体的隔离和净化.
- 使用核磁共振 (NMR) 光谱学阐明结构.
- 用X射线衍射 (XRD) 分析进行结构确认.
主要成果:
- 对于trifluoromethylpyrazoles的区域选择性合成所确定的反应条件.
- 确定了水替代剂在指导化中的作用.
- 成功地分离和表征了由bis-pyrazolyl NH-ketazine基化形成的各种区域异构体.
- 通过全面的光谱和晶体学数据证实了合成化合物的结构.
结论:
- 子替代剂是有效的指导组,用于控制三甲基pyrazoles中的N-化区域选择性.
- 开发的方法允许针对特定的pyrazole区域异构体进行有针对性的合成.
- 这项工作为异环化合物的N功能化提供了宝贵的见解.
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