通过差异化中间激活,增强了素结合对素结合的选择性 催化C-糖化通过差异化中间激活
1College of Chemistry and Materials Science, Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, 510632, P.R. China.
Angewandte Chemie (International ed. in English)
|November 13, 2025
概括
与素结合 (XB) 催化相比,素结合 (ChB) 催化在-C-糖化中具有更高的选择性. 这种增强的立体控制源于独特的下游激活机制,涉及多个 σ-洞.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 催化剂是一种催化剂.
背景情况:
- σ-孔相互作用,包括素结合 (ChB) 和素结合 (XB),对于立体选择性合成至关重要.
- 在糖基化中,ChB与XB的催化效率差异的机制基础尚不清楚.
- -C-糖化是碳水化合物合成中的关键转化,需要精确的立体化学控制.
研究的目的:
- 与XB催化相比,研究基化物 (PCH) 催化在基化中的优异性能.
- 阐明控制ChB与XB催化甘氨基化中的立体选择性的机制差异.
- 了解 σ-孔相互作用在控制反应路径和立体化学结果中的作用.
主要方法:
- 对基化物 (PCH) 催化和素结合 (XB) 催化在基化中的比较研究.
- 机理学研究包括哈梅特分析,以探测反应机制 (SN1与SN2).
- 密度函数理论 (DFT) 计算来分析σ孔相互作用和中间激活.
主要成果:
- 通过PCH催化,与XB催化相比,在aryl-C-glycosylations中显著提高了选择性和反应性.
- 机械研究表明,ChB催化促进了SN1通路,而XB催化则有利于SN2通路.
- DFT的计算显示,所有四个 σ-洞都在二叉的ChB模式中进行了独特的激活,导致了差异化的中间激活.
结论:
- 素结合催化提供了明显的机械优势,使得在-C-糖化中能够进入高度立体选择的途径.
- 在ChB催化中,增强的立体控制归因于涉及多个σ孔的特定下游激活模式.
- 这项研究澄清了ChB催化的机械基础,突出了其对先进立体选择性碳水化合物合成的潜力.
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