针对难以捉摸的四氨基二烯的可能策略
Thomas Müller1, Yitzhak Apeloig
1Institut für Anorganische Chemie der Goethe Universität Frankfurt, Marie Curie-Strasse 11, D-60439 Frankfurt/Main, Federal Republic of Germany. Dr.Thomas.Mueller@chemie.uni-frankfurt.de
Journal of the American Chemical Society
|March 28, 2002
概括
量子力学计算预测,特定的二氨基烯可以二聚变,形成稳定的四氨基烯. 这项研究确定了影响单三能量差异的关键结构因素,指导了这些难以捉摸的化合物的合成.
科学领域:
- 无机化学 无机化学 有机化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 氨基烯是反应性中间体.
- 四氨基二烯 (tetraaminodisilenes) 是二氨基二烯的二元,它们非常受欢迎,但很难合成.
- 二元化过程受到二氨基烯的电子和结构性质的影响.
研究的目的:
- 为了预测哪些二氨基烯可以二元化形成稳定的四氨基烯.
- 了解分子结构与四氨基二烯的稳定性之间的关系.
- 为了指导强键四氨基二烯的实验合成.
主要方法:
- 使用了量子力学计算.
- 用B3LYP函数和6-311++G(3df,2p) 基础集的密度函数理论 (DFT) 用于几何优化.
- 对于能量计算,使用了具有6-31G(d) 基数的第二阶Møller-Plesset扰动理论 (MP2).
- 计算了单元-三元能量差异 (ΔE(ST)) 和二元化能量 (E(dim)).
主要成果:
- 双氨基烯的单元-三元能量差异 (ΔE(ST)) 在很大程度上取决于SiN2和R2N平面之间的扭曲角度 (φ) 和NSiN结合角度 (α).
- 扭曲的增加 (较大的φ) 和α的扩大导致 ΔE (ST) 的减少.
- 预计双循环氨基烯和基替代氨基烯会形成具有显著Si=Si键长度的稳定四氨基烯.
结论:
- 理论预测表明,特定的二氨基烯可以合成形成稳定的四氨基烯.
- 结构修改,如增加扭转和更宽的结合角度,对于实现稳定的二度体至关重要.
- 这项研究为未来的强键四氨基二烯合成提供了理论基础.
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