Bis(methylene)-λ⁵-phosphane anions, i.e., anionic phosphorus-centered heteroallene-type molecules, were obtained from the desilylation of a bis(silyl)methyl-substituted phosphaalkene. Their molecular structures, which were determined using spectroscopic techniques and single-crystal X-ray diffraction analysis, suggest that the central di-coordinated P atom is engaged in cumulative CPC π-bonds with the neighboring C atoms. The π-bond character of the CPC moieties was examined on the basis of the experimental results in combination with theoretical calculations; the results obtained suggest that multiple silyl substitutions at the C atom weaken the CP π-bonding character.

中文翻译：

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双（亚甲基）-λ5-膦阴离子


双（亚甲基）-λ⁵-膦阴离子，即阴离子磷中心杂丙烯型分子，是从双（硅烷基）甲基取代的磷烷基化中获得的。它们的分子结构是使用光谱技术和单晶 X 射线衍射分析确定的，表明中心双配位 P 原子与相邻的 C 原子进行累积的 C P C π键。根据实验结果结合理论计算，研究了 C P C 部分的π键特性;获得的结果表明，C 原子处的多个甲硅烷基取代削弱了 C P π键特性。