Riu Martin-Louis Y, Jones Rebecca L, Transue Wesley J, Müller Peter, Cummins Christopher C
Department of Chemistry, Massachusetts Institute of Technology, Cambridge MA, USA.
Sci Adv. 2020 Mar 25;6(13):eaaz3168. doi: 10.1126/sciadv.aaz3168. eCollection 2020 Mar.
This exploratory synthesis investigation was undertaken to determine the viability of replacing a single carbon vertex with another p-block element in a highly strained tetrahedrane molecule. Phosphorus was selected for this purpose because the stable molecular form of elemental phosphorus is tetrahedral. Our synthetic strategy was to generate an unsaturated phosphorus center bonded to a substituted cyclopropenyl group, a situation that could lead to closure to provide the desired phosphatetrahedrane framework. This was accomplished by dehydrofluorination of the in situ generated fluorophosphine H(F)P(C Bu). Tri--butyl phosphatetrahedrane, P(C Bu), was then isolated in 19% yield as a low-melting, volatile, colorless solid and characterized spectroscopically and by a single-crystal x-ray diffraction study, confirming the tetrahedral nature of the molecule's PC core. The molecule exhibits unexpected thermal stability.
进行这项探索性综合研究是为了确定在高度应变的四面体烷分子中用另一种p区元素取代单个碳顶点的可行性。为此选择了磷，因为元素磷的稳定分子形式是四面体。我们的合成策略是生成一个与取代环丙烯基相连的不饱和磷中心，这种情况可能导致闭环以提供所需的磷四面体烷骨架。这是通过原位生成的氟膦H(F)P(C Bu)的脱氟化氢反应来实现的。然后以19%的产率分离出三丁基磷四面体烷P(C Bu)，它是一种低熔点、挥发性、无色固体，并通过光谱和单晶X射线衍射研究进行了表征，证实了分子的PC核心的四面体性质。该分子表现出意想不到的热稳定性。
