部分桥式化二甲基双环[1.1.1]-1,3-二碳酸盐:制剂和NMR光谱
A B Shtarev1, E Pinkhassik, M D Levin
1Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215, USA.
Journal of the American Chemical Society
|July 27, 2001
概括
研究人员通过直接化合成了14种桥式化双循环[1.1.1]坦衍生物. 聚化显著增加了子应变,特定的安排导致了最高的应变能量.
科学领域:
- 有机化学 有机化学
- 化学 的化学
- 计算化学计算化学
背景情况:
- 自行车[1.1.1]坦是具有独特结构性质的紧张子化合物.
- 直接化提供了一种途径,将原子引入有机分子.
- 了解替代对应力系统的影响对于开发新材料和药品至关重要.
研究的目的:
- 为了合成和表征桥式化双环[1.1.1]-1,3-二碳酸.
- 为了研究多化对自行车[1.1.1]坦芯应变能量的影响.
- 分析光谱特性 (NMR) 并将它们与计算计算相关联.
主要方法:
- 改善了 [1.1.1] 烯及其二碳酸衍生物的合成.
- 直接化二甲基双环[1.1.1]坦-1,3-二碳酸盐.
- 使用准备性气相色谱 (GC) 隔离和净化产品.
- 计算化学方法 (GIAO-RHF,MP2,EOM-CCSD) 用于几何和NMR属性计算.
主要成果:
- 在15种可能的桥式化双环[1.1.1]-1,3-二碳酸中,合成了14种.
- 计算的几何形状与本特规则一致,反映了替换模式.
- 聚化引入显著的应变,高达33-35 kcal/mol的六次替代.
- 核磁共振光谱显示了各种化学转移和长距离合常量,与计算非常一致.
- 观察到大型近距离 (4) J FF 合常量 (50-100 Hz),与 F-F 距离相对依赖.
结论:
- 直接化是一种有效的方法,可以获得多化bicyclo[1.1.1]pentanes.
- 多化极大地增加了bicyclo[1.1.1]pentane中的压力.
- 计算方法准确地预测了这些应力,化系统的结构和光谱特性.
- 观测到的NMR合常数为应力化分子中通过空间相互作用提供了宝贵的见解.
相关概念视频
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