Use of Molecular Scaffolding for the Stabilization of an Intramolecular Dative PIII-PV System
Use of Molecular Scaffolding for the Stabilization of an Intramolecular Dative PIII-PV System
复制标题
使用分子支架稳定分子内配位 PIII-PV 系统
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
J. Woollins
中科院分区：
文献类型：
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作者：
P. Kilian;D. Philp;A. Slawin;J. Woollins
NaP_2S_4(1；NAP=萘-1，8-二基)与氯气反应生成[NAP(PCl_2)(PCl_4)](2)，表现出罕见的σ4P-σ6P键相互作用。X-射线结构分析证实了晶体中含有磷-磷化物结构的PCl5，P-−P键，在低温溶液中也发现了这种结构。在常温和高温下，观察到了核磁共振时间尺度上的动态行为，归属为离子磷磷化物形式2和分子双(膦)NAP(PCl_3)_2形式3的互换，而不是离子膦盐-磷烷形式[NAP(PCl_3)(PCl_2)][Cl]_4。在B3LYP/6−31G(d，p)理论水平上对结构2和3进行了电子结构计算；结构3位于势能面上的局部极小值，能量比结构2高15kcal·−。2和3的晶体结构和计算的P−P距离分别为2.34和2.31 A。通过坐标驱动计算得到过渡态结构的活化能为19.7kcal·mol−1，变温31p{1H}核磁共振谱的线形分析得到活化能为14.4kcal·moL−1。
The reaction of NapP2S4 (1; Nap = naphthalene-1,8-diyl) with chlorine gas gave [Nap(PCl2)(PCl4)] (2), displaying a rare σ4P-σ6P bonding interaction. An X-ray structure analysis confirmed the PCl5-like, P−P bond containing phosphonium-phosphoride structure of 2 in the crystal, which was also found in solution at low temperature. At ambient and higher temperatures, dynamic behaviour on the NMR time-scale was observed, which was assigned to interchange of the ionic phosphonium-phosphoride form 2 and the molecular bis(phosphorane) Nap(PCl3)2 form 3, rather than to the ionic phosphonium salt-phosphorane form [Nap(PCl3)(PCl2)][Cl] 4. Electronic structure calculations were performed at the B3LYP/6−31G(d,p) level of theory on structures 2 and 3; structure 3 was located as a local minimum on the potential energy surface, 15 kcal·mol−1 higher in energy than structure 2. The crystal structure and calculated P−P distances are 2.34 and 2.31 A for 2 and 3, respectively. An activation energy of 19.7 kcal·mol−1 was found for the transition state structure by coordinate driving calculations; the line-shape analysis of variable temperature 31P{1H} NMR spectra gave an activation energy of 14.4 kcal·mol−1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)