在dialkoxy二硫化物 (ROSSOR) 和硫酸硫化物 ((RO) 2S=S) 之间的交叉点:预测,合成和结构
Eli Zysman-Colman1, Neysa Nevins, Nicolas Eghbali
1Department of Chemistry, McGill University, Montreal, Quebec, Canada H3A 2K6.
Journal of the American Chemical Society
|January 5, 2006
概括
环大小决定了循环二氧化硫化和硫酸硫酸盐的异构偏好. 较小的环更喜欢硫酸硫酸盐,而较大的环和非循环化合物更喜欢二氧化硫酸二硫酸盐,已确定酸催化异构化途径.
科学领域:
- 有机化学 有机化学
- 异环化学 异环化学
- 计算化学计算化学
背景情况:
- 在dialkoxy二硫化物和thionosulfites之间的同位素关系还没有完全理解.
- 根据结构特征预测这些同位素的稳定性和形成是具有挑战性的.
研究的目的:
- 为了研究环形大小对循环二氧化硫化物和硫酸硫酸盐之间的同位素偏好的影响.
- 确定这些构成性异构体之间的稳定性交叉点.
- 阐明这些化合物之间的异构化机制.
主要方法:
- 用密度函数计算来预测异构体的相对稳定性.
- 进行了新型循环化合物的合成.
- 采用X射线晶体学和核磁共振 (NMR) 光谱来进行结构性表征.
主要成果:
- 环的大小决定了同位素的偏好:较小的环 (<7个原子) 更喜欢硫酸硫酸盐,而较大的环 (>7个原子) 和非循环类似物更喜欢二氧化硫化物.
- 合成了以前未知的八个成员的dialkoxy disulfide和七个成员的thionosulfite.
- 使用X射线结晶学和NMR分析了固态和溶液构造.
- 发现异构化途径依赖于酸.
结论:
- 环大小是循环二氧化硫化物和硫酸硫酸盐中异构体偏好的关键决定因素.
- 计算和合成研究为这些异环化合物的稳定性和形成提供了新的见解.
- 异构化机制受到酸催化作用的影响,为它们的化学行为提供了更深入的理解.
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