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从循环 () (氨基) 碳化合物中衍生出的空气持久的单体 (氨基) 碳基基
Janell K Mahoney1, David Martin1,2, Fabrice Thomas2
1†UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0343, United States.
Journal of the American Chemical Society
|May 27, 2015
概括
新的 (氨基) 基和碳基基基具有吸收电子的碳基基团,显示出增强的稳定性,在溶液中持续数天. 它们的电子特性发生变化,影响它们与氧的反应性.
科学领域:
- 有机化学 有机化学
- 激进化学 激进化学是什么
- 计算化学计算化学
背景情况:
- 单质 (氨基) 基和碳基基原先被认为是高度对空气敏感的.
- 循环 (基) 氨基) 碳化合物 (CAACs) 是激素合成的稳定前体.
研究的目的:
- 用不同的取电子的碳基替代剂合成新的 (氨基) 基和碳氧基.
- 为了研究这些基的稳定性和电子性质.
- 探索替代剂对基质反应,特别是对二氧化物的影响.
主要方法:
- 从稳定的循环 (基) (氨基) 碳化合物 (CAAC) 中合成单体 (氨基) 碳基基,两到三步.
- 在空气溶液中合成的基因的稳定性评估.
- 密度函数理论 (DFT) 计算用于分析电子结构和反应能量.
主要成果:
- 成功合成了一系列 (氨基) 基 (碳基) 基 (3a-3e) 随着电子提取碳基替代剂的增加.
- 在空气溶液中观察到增强的稳定性,半衰期为小时 (3d) 和天 (3c,3e),与之前的假设相反.
- DFT的计算显示,从以C为中心的C,O-激进分子转变为两极性C,O-激进分子,其电子吸收强度越来越大.
- 预测过氧化物形成的破坏稳定和内热反应,在添加二氧化物时为高度缺乏电子的激素.
结论:
- 提取电子的碳基替代剂显著提高了 (氨基) 基的稳定性.
- 替代物的电子性质决定了基的性质及其对氧的反应性.
- 这些发现为在合成化学中利用更稳定的基质物种开辟了道路.
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