A MODEL FOR CALCULATING CONFORMATIONAL ENERGIES IN PENTACOORDINATE PHOSPHORUS COMPOUNDS
A MODEL FOR CALCULATING CONFORMATIONAL ENERGIES IN PENTACOORDINATE PHOSPHORUS COMPOUNDS
复制标题
计算五配位磷化合物构象能的模型
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
R. R. Holmes
中科院分区：
文献类型：
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作者：
R. R. Holmes
摘要建立了一个模型，可以估计给定五配位磷化合物的所有三角双锥体（TP）和方锥体（SP）异构体的相对稳定性。它是基于广泛使用的伪旋转假设。该模型利用控制已知结构的简单无环衍生物的流动行为的活化能以及定义TP-SP能量差的理论和光谱研究结果。基于这些标准，构建了TP和SP的亲尖性尺度，并附加了它们具有相同范围和作为配体电负性函数彼此线性相关的约束。结合环应变和空间项的所得模型具有普遍适用性，对磷反应机理中五坐标中间体和过渡态的量化具有相当的预测价值。该模型给出的相对同分异构体能量与…
Abstract A model is developed which allows the estimation of the relative stability of all trigonal bipyramidal (TP) and square pyramidal (SP) isomers of a given pentacoordinate phosphorus compound. It is based on the widely used pseudorotational hypothesis. The model makes use of activational energies governing fluxional behavior for simple acyclic derivatives of known structure and results of theoretical and spectroscopic studies defining TP-SP energy differences. Based on these criteria, apicophilicity scales are constructed for the TP and SP with the additional constraints that they have the same range and correlate linearly with each other as a function of ligand electronegativity. The resultant model which incorporates ring strain and steric terms has general applicability and should prove of considerable predictive value in quantifying pentacoordinate intermediates and transition states postulated in phosphorus reaction mechanisms. The model gives relative isomer energies in excellent agreement wit...