一个稳定的同源的高度紧张的bicyclo[3.2.0]hepta-1,3,6-triene的1,3,6-三烯
Yoshihiro Kon1, Jun Ogasawara, Kenkichi Sakamoto
1Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.
Journal of the American Chemical Society
|August 2, 2003
概括
研究人员合成了一种含有的双循环化合物,具有独特的双键结构. 尽管有很大的压力,但重的替代品提供了显著的稳定性,使其能够在空气中持续数月.
科学领域:
- 有机化学 有机化学
- 合成有机化学 合成有机化学
- 应变理论 应变理论
背景情况:
- 化自行车系统具有独特的结构和电子特性.
- 高应力有机分子挑战了传统的稳定性范式.
- 融入有机框架可以导致新的反应性和稳定性.
研究的目的:
- 为了合成和表征一种含有的新型化双环化合物,具有紧张的桥头双键.
- 研究有机化合物中高固体应变的结构和稳定性影响.
- 在应力系统中探索固体体积和分子稳定性之间的关系.
主要方法:
- 通过与二三-丁cyclopropenone的反应,通过一个 silatriafulvene 的定量合成.
- 进行X射线晶体分析,以确定精确的分子结构和结合角度.
- 计算建模 (MP2/B3LYP) 用于计算应变能量.
主要成果:
- 成功合成了2,3,6,7-tetra-tert-butyl-4- (((tert-butyldimethylsilyl) -5- (((tert-butyldimethylsiloxy) -5-silabicyclo[3.2.0]hepta-1,3,6-triene (2) 的二,三,六,六,六,六,六,六,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,七,八,七,七,七,八,七,八,八,八,七,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,八,
- X射线分析证实了合的和环系统,具有显著的双键变形 (桥头碳键角度总和为333°).
- 计算的应变能量 (30.2 kcal/mol) 与其碳循环类比相比,表明固有的高应变.
结论:
- 合成的化合物表现出高度紧张的双循环烯结构.
- 尽管极端应变,该分子表现出了显著的空气稳定性,这是由于对体积大大的 tert-butyl 和 tert-butyldimethylsilyl 基的固体保护.
- 这项研究强调了通过战略替代物放置来稳定高压力有机化合物的潜力.
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