在热力学控制下对1,2,3-三醇与以太的基化
Hui Zhang1, Zijian Zhang2, Lifang Tian2
1School of Chemistry and Chemical Engineering, Zhoukou Normal University, Wenchang Road, Zhoukou 466001, China.
Organic letters
|January 31, 2025
概括
这项研究引入了一种新的方法,用于使用乙醇化三醇. 该过程涉及氧化交叉脱配合和异构化,导致热力学稳定的N2-化三醇.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
背景情况:
- 三醇基化是有机合成中的一个基本转化.
- 控制二醇化中的区域选择性,特别是实现N2化,仍然是一个挑战.
研究的目的:
- 开发一种新的中继策略,用于用乙醇对三醇进行N2选择性化.
- 为了在热力学控制条件下实现这种选择性.
主要方法:
- 采用了将氧化交叉脱联结合 (CDC) 和N1-到N2-异构化相结合的中继策略.
- 反应是由N1-和N2-化三醇 (3.65 kcal/mol) 之间的热力学稳定性差异驱动的.
- 利二甲酸 (PhI(OAc) 2被用作双重功能试剂,同时作为氧化剂和异构化媒介.
主要成果:
- 开发的策略成功地实现了三醇与的正式N2选择性化.
- 最初形成的N1异构体在热力学平衡下被有效地*in situ*转化为它们更稳定的N2异构体.
- PhI(OAc) 2在CDC和异构化步骤中都被证明是有效的.
结论:
- 发现的中继策略为N2选择性三醇化提供了一个强大的方法.
- 这种方法利用热力学控制有利于形成更稳定的N2-基化产品.
- PhI(OAc) 2的双重作用简化了反应系统并提高了它的效率.
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