The reactivity of the geminal phosphinoborane tBu₂PCH₂BPh₂ towards terminal alkynes, nitriles and nitrilium salts is investigated. Terminal alkynes react via C–H bond splitting (deprotonation) resulting in the formation of phosphonium borates. In contrast, both nitriles and nitrilium salts undergo addition reactions resulting in the formation of five-membered heterocycles. All compounds were characterized by multinuclear NMR spectroscopy, and single-crystal X-ray structure determinations. Insight into the reaction mechanisms was gained by DFT calculations.

中文翻译：

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双膦膦硼烷t Bu ₂ PCH ₂ BPh ₂对炔烃，腈和三氟甲磺酸盐的反应性

研究了双膦膦硼烷t Bu ₂ PCH ₂ BPh ₂对末端炔烃，腈和腈盐的反应性。末端炔烃通过C–H键分裂（去质子化）反应，导致形成硼酸phospho。相反，腈盐和腈盐都经历加成反应，导致形成五元杂环。所有化合物均通过多核NMR光谱和单晶X射线结构测定进行表征。通过DFT计算可以深入了解反应机理。