通过电荷转移晶体的迪尔斯-阿尔德拓化学:新的 (热) 单晶到单晶的转换
J H Kim1, S M Hubig, S V Lindeman
1Department of Chemistry, University of Houston, Houston, Texas 77204-5641, USA.
Journal of the American Chemical Society
|March 29, 2001
概括
这项研究揭示了一种罕见的单相固态循环添加反应. 晶体结构指导反应,形成一个独特的产品修改与加速动力学.
科学领域:
- 固态化学 固态化学
- 有机化学 有机化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 固态反应为化学转化提供了独特的途径.
- 拓化学控制决定了晶体环境中的反应结果.
- 电荷转移晶体可以促进分子间反应.
研究的目的:
- 为了研究固态 [4+2] 循环添加反应的机制.
- 分析晶体包装在控制反应路径和产品形成中的作用.
- 在反应过程中将晶体学变化与动力学数据相关联.
主要方法:
- 单晶X射线衍射用于监测结构变化.
- 1H NMR光谱检测以获得温度依赖的动力数据.
- 对分子间电荷转移晶体反应的分析.
主要成果:
- 观察到一种独特的单相 topochemical [4+2] 循环添加甲到 bis ((N-ethylimino) -1,4-dithiin.
- 反应是通过整个晶体内的热异分子凝结进行的.
- 形成了Diels-Alder产品的新晶体修饰,保留了与反应剂相似的晶体包装.
- 反应动力学显示随着时间的推移由于降低激活屏障而加速.
结论:
- 固态反应可以通过晶格精确控制.
- 拓化学控制导致独特的产品多态,无法在溶液中获得.
- 晶体中的单相转换为研究反应机制和动力学提供了一个独特的平台.
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