Treatment of the trilithium compounds 3 with PCl₃ afforded sterically constrained tricyclic phosphines with annulated five‐ (2 ×) and six‐membered rings and the P atoms in the bridgehead positions (2a, vinylic SiMe₂Ph; 2b, vinylic SiMe₃ groups). Their AuCl complexes (4) were used for an estimation of the buried volumes (4b: %V = 46 %). Reactions of 2b with XeF₂ or SO₂Cl₂ afforded PX₂ derivatives [X = F (5b), Cl (6b)]. Crystal structure determinations including the recently reported difluorides and diiodides of 2a (5a and 7) allow a systematic comparison of structural details. The P atoms have trigonal bipyramidal to square pyramidal surroundings. The PF₂ phosphorane 5a behaves as a Lewis acid and coordinates F^– to yield a phosphate anion (8) with a PF₃C₃ molecular centre, while Cl^– abstraction from 3a afforded an unstable phosphonium cation (9). Unusual methylphosphoranes with one or two methyl groups attached to phosphorus were obtained by reactions of the dihalides 5a or 6a with methyllithium.

中文翻译：

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立体约束的三环膦的二卤化物，路易斯酸度和氟化物亲和力，氯化物的提取以及os阳离子的二甲基磷烷

用PCl ₃处理三锂化合物3可得到空间受限的三环膦，其环带五（2×）和六元环，桥头位置具有P原子（2a，乙烯基SiMe ₂ Ph；2b，乙烯基SiMe ₃基团） 。他们的AuCl配合物（4）用于估计埋藏量（4b：％V = 46％）。的反应图2b用的XeF ₂或SO ₂氯₂得到PX ₂衍生物[X = F（图5b），CL（图6b）]。晶体结构的确定，包括最近报道的2a（5a和7）的二氟化物和二碘化物，可以对结构细节进行系统的比较。P原子具有三角双锥体到方形锥体的周围环境。所述PF ₂膦5a中表现为路易斯酸和坐标F ^- ，得到磷酸根阴离子（8）与一个PF ₃ Ç ₃分子中心，而氯^-从抽象3a中得到一个不稳定的鏻阳离子（9）。通过二卤化物5a或6a与甲基锂的反应获得了具有一个或两个与磷相连的甲基的不寻常的甲基磷烷。