Zhu Cheng, Eckhardt André K, Chandra Sankhabrata, Turner Andrew M, Schreiner Peter R, Kaiser Ralf I
Department of Chemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI, 96822, USA.
W. M. Keck Laboratory in Astrochemistry, University of Hawaii at Manoa, 2545 McCarthy Mall, Honolulu, HI, 96822, USA.
Nat Commun. 2021 Sep 15;12(1):5467. doi: 10.1038/s41467-021-25775-1.
Polyhedral nitrogen containing molecules such as prismatic PN - a hitherto elusive isovalent species of prismane (CH) - have attracted particular attention from the theoretical, physical, and synthetic chemistry communities. Here we report on the preparation of prismatic PN [1,2,3-triaza-4,5,6-triphosphatetracyclo[2.2.0.0.0]hexane] by exposing phosphine (PH) and nitrogen (N) ice mixtures to energetic electrons. Prismatic PN was detected in the gas phase and discriminated from its isomers utilizing isomer selective, tunable soft photoionization reflectron time-of-flight mass spectrometry during sublimation of the ices along with an isomer-selective photochemical processing converting prismatic PN to 1,2,4-triaza-3,5,6-triphosphabicyclo[2.2.0]hexa-2,5-diene (PN). In prismatic PN, the P-P, P-N, and N-N bonds are lengthened compared to those in, e.g., diphosphine (PH), di-anthracene stabilized phosphorus mononitride (PN), and hydrazine (NH), by typically 0.03-0.10 Å. These findings advance our fundamental understanding of the chemical bonding of poly-nitrogen and poly-phosphorus systems and reveal a versatile pathway to produce exotic, ring-strained cage molecules.
多面体含氮分子，如棱柱状的PN（一种迄今为止难以捉摸的棱晶烷（CH）的等电子体），引起了理论化学、物理化学和合成化学界的特别关注。在此，我们报告了通过将磷化氢（PH）和氮气（N）冰混合物暴露于高能电子来制备棱柱状PN[1,2,3-三氮杂-4,5,6-三磷杂四环[2.2.0.0.0]己烷]的方法。在气相中检测到了棱柱状PN，并在冰升华过程中利用异构体选择性、可调谐软光电离反射式飞行时间质谱将其与异构体区分开来，同时进行了异构体选择性光化学处理，将棱柱状PN转化为1,2,4-三氮杂-3,5,6-三磷杂双环[2.2.0]己-2,5-二烯（PN）。在棱柱状PN中，与例如联膦（PH）、二蒽稳定化的磷单氮化物（PN）和肼（NH）中的P-P、P-N和N-N键相比，其键长通常延长了0.03 - 0.10 Å。这些发现推进了我们对多氮和多磷体系化学键的基本理解，并揭示了一条制备奇特的、环张力笼状分子的通用途径。
