A carboranyl-based meso-1,2,5-selenadiphospholane diselenide was synthesised starting from a strained carborane-substituted 1,2-diphosphetane and subsequently reduced to an unprecedented carboranyl-based meso-1,2,5-selenadiphospholane. The electronic structure and the bonding situation for both compounds were investigated by density functional theory (DFT), Natural Bond Orbital (NBO) analyses, Fractional Occupation Density (FOD) analysis, Complete Active Space Self Consistent Field (CASSCF) calculations and time-dependent DFT (TDDFT) calculations. Ring-opening reactions of meso-1,2,5-selenadiphospholane with nucleophiles and electrophiles are reported together with calculated reaction mechanisms (DFT level). Isolated compounds were characterised by NMR and IR spectroscopy, high-resolution mass spectrometry, elemental analysis and single-crystal X-ray diffraction.

中文翻译：

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开发二膦环化合物的环菌株：一种合成和计算方法，用于1,2,5-硒代二膦酸酯。

从应变的碳硼烷取代的1,2-二膦烷开始合成了基于碳硼烷基的内消旋1,2,5-硒代戊二烯二硒化物，随后将其还原为空前的基于碳硼烷基的内消旋1,2,5-硒代二戊烷。通过密度泛函理论（DFT），自然键轨道（NBO）分析，分数职业密度（FOD）分析，完全活动空间自洽场（CASSCF）计算和时间依赖性研究了这两种化合物的电子结构和键合情况DFT（TDDFT）计算。报道了内消旋1,2,5-5-硒二膦烷与亲核试剂和亲电试剂的开环反应以及计算的反应机理（DFT水平）。分离出的化合物通过NMR和IR光谱，高分辨率质谱进行表征，