在气相中是一个稳定的aminothioketyl基
Magdalena Zimnicka1, Joshua A Gregersen, František Tureček
1Department of Chemistry, University of Washington, Bagley Hall, Box 351700, Seattle, Washington 981195-1700, USA.
Journal of the American Chemical Society
|May 28, 2011
概括
研究人员通过电子转移准备了一种稳定的aminothioketyl基. 这种极端的激进主义.
科学领域:
- 化学物理 化学物理
- 有机化学 有机化学
- 质谱测量质量谱测量
背景情况:
- 氨基基基是激素化学中的关键中间体.
- 了解它们的稳定性和反应性对于各种化学应用至关重要.
- 之前的研究缺乏对这些特定的根性物种的详细表征.
研究的目的:
- 报告一种稳定的aminothioketyl基的第一个制剂.
- 通过先进的计算和实验方法来描述其结构和电子特性.
- 阐明单分子解离路径和能量依赖.
主要方法:
- 快速的电子转移到气相中的质子化硫乙胺.
- 中和-再电离质谱法用于基质的表征.
- 高层次的初始计算 (例如,CCSD) /aug-cc-pVTZ) 和RRKM理论用于解离分析.
- 乳标记研究,以追踪解离路径.
主要成果:
- 成功制备和表征一个稳定的aminothioketyl基,CH ((3) C (((•) ((SH) NHCH ((3).
- 确定了两个具有竞争力的单分子解离途径:丢失硫原子和丢失N-甲基组.
- 确定S-H键裂变在较低的内部能量时占主导地位,而N-CH(3) 键裂变在更高的能量时占主导地位.
- 计算了原子添加到胺硫的非常低的激活能量,这表明原子的捕获作用.
结论:
- 可以生成和表征稳定的aminothioketyl基.
- 分离途径依赖于能量,对低内部能量和高内部能量有明显的偏好.
- 这些发现对在蛋白质研究中理解硫基和离子基有意义,它们可能作为原子陷.
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