具有强极化P-P键的二素:共价分子和具有灵活分子结构的捐赠-接受 adducts 之间的混合物
Sebastian Burck1, Kathrin Götz, Martin Kaupp
1Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70550 Stuttgart, Germany.
Journal of the American Chemical Society
|July 3, 2009
概括
研究人员探索了以P-醇替代的N-异环,揭示了高度灵活的P-P键. 这些债券表现出可变的长度和独特的特征,挑战了传统的共价债券分类.
科学领域:
- 有机金属化学 有机金属化学
- 酸盐化学 酸盐化学
- 固态化学 固态化学
背景情况:
- 在有机金属化学中,N-异环氨酸是关键的配体.
- 了解PP键的性质对于设计新的化合物至关重要.
研究的目的:
- 为了合成和表征P-基替代的N-异环氨酸.
- 研究这些化合物中PP债券的结构和电子特性.
- 探索影响PP键长度和合常数的因素.
主要方法:
- 单晶X射线衍射用于结构分析.
- 溶液和固态 31P 核磁共振 (NMR) 光谱学.
- 计算研究 (例如密度函数理论).
- 对二极合常量进行双量子脱相 (DoDe) 实验.
主要成果:
- 合成和表征了一系列P-醇替代的N-异环氨酸.
- 观察到异常可变的P-P键长度 (2.35-2.70 Å),远远超过典型的共价距离.
- 证明了P-P键长度,费米接触贡献,以及1J (PP) 合常数的大小和符号之间的相关性.
- 在溶液和固态NMR之间的1J (PP) 值中发现了差异,以及溶液中的温度依赖.
结论:
- 由于平坦的潜在能源盆地,PP债券表现出显著的灵活性.
- 这种PP债券可以被归类为"衍生债券",而不是正常的共价债券.
- 这些化合物代表了共价双和-接触离子对之间的混合物.
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