通过碎片凝结方法合成单体甲基[4]arene
Daniel Kortus1, Oliver Moravec1, Hynek Varga1
1Department of Organic Chemistry, University of Chemistry and Technology Prague (UCTP), Technická 5, 166 28 Prague, Czech Republic.
Molecules (Basel, Switzerland)
|August 14, 2025
概括
一种用于制备混合桥接 (CH2和S) [4]的新方法提供了高产. 可变温度的NMR研究揭示了这些宏观循环中的动态行为和键的洞察力.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 宏观循环化学 宏观循环化学
背景情况:
- 卡利克斯[4]是多功能宏循环平台.
- 含硫的混合桥梁[4]沙具有独特的结构和动态特性.
- 了解形状动态对于设计功能宏循环至关重要.
研究的目的:
- 为了开发一个简单的和可扩展的合成2-monothiacalix[4]arene.
- 为了研究合成的宏循环及其氧化衍生物的动态行为.
- 阐明硫合并和氧化对宏环形状和结合的影响.
主要方法:
- 通过线性双醇的凝结合成.
- 可变温度的核磁共振 (NMR) 光谱学.
- 动态过程的计算分析 (圆-圆倒置,翻转机械).
主要成果:
- 通过使用两个替代途径,成功制备了高产量的2-monothiacalix[4]arene (7).
- 对化合物7 (ΔG‡ = 63 kJ·mol−1) 和其硫衍生物14 (ΔG‡ = 60 kJ·mol−1) 的圆平衡和反转障碍的确定.
- 在低温下 (ΔG‡ = 44 kJ·mol−1对于7而不是 ΔG‡ = 40 kJ·mol−1对于14) 的翻转键机制的障碍物的量化,表明硫中的键被削弱了.
结论:
- 开发的合成策略有效地生产混合桥梁[4]arenes.
- 硫的结合和氧化影响着在卡利克萨林框架内的结构动态和结.
- 这些发现为含硫宏循环的结构性质关系提供了宝贵的见解.
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