光催化对内分甘油的 perfluoroalkylation 进行光催化
Erwin W Mora Flores1,2,3, Daniel Suarez1,2,3, María Laura Uhrig1,2
1Universidad de Buenos Aires, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina.
The Journal of organic chemistry
|December 5, 2023
概括
可见光光催化使得糖衍生物的 perfluoroalkylation 成为可能. 一个与葡萄糖结合的催化剂通过激素连锁反应意外形成了1- perfluoroalkyl-2- iodo C-glycosyl产物.
科学领域:
- 有机化学 有机化学
- 光催化作用的光催化
- 碳水化合物化学 碳水化合物化学
背景情况:
- perfluoroalkyl (RF) 组在制药和材料科学中至关重要.
- 可见光光催化剂为激素生成和功能化提供了一个可持续的方法.
- 糖醇是复杂分子合成的多功能碳水化合物构建块.
研究的目的:
- 为了研究可见光诱导的对 peracetylated glycals 的 perfluoroalkylation 反应.
- 探索使用各种光催化剂和 perfluoroalkyl iodides (RF-I) 进行RF基的产生.
- 阐明这些转换的反应机制和区域选择性.
主要方法:
- 使用LED作为辐射源的光催化基反应.
- 使用不同的光催化剂,包括复合物和有机染料.
- 使用 perfluoroalkyl 化物 (RF-I) 作为 perfluoroalkyl 基的来源.
- 合成和特征的产品来自hexose和pentose糖基.
主要成果:
- 葡萄糖衍生物的 perfluoroalkylation 产生了两种不同的产品: 2-RF - 替代的葡萄糖和一个新的1-RF-2-iodo-α-manno - 配置的C-glycosyl衍生物.
- 1-RF-2-产物是RF部分对异构碳的区域选择性添加的结果,随后在C-2处进行轴性化.
- 通过银糖,阿拉比诺糖和西洛糖的 perfluoroalkylation 主要通过乙烯基替代产生2-RF替代产品.
结论:
- 这项研究展示了一种新的光催化方法,用于将 perfluoroalkyl 组引入糖性支架上.
- 机械洞察力揭示了不同的途径:对1-RF-2-产品的激进链反应和对2-RF替代糖的低效链过程.
- 这些发现突显了光催化在碳水化合物功能化中的潜力,提供了独特的C-glycosyl衍生物.
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