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The elusive cyclotriphosphazene molecule and its Dewar benzene-type valence isomer (P₃N₃).

ABSTRACT: Although the chemistry of phosphorus and nitrogen has fascinated chemists for more than 350 years, the Hückel aromatic cyclotriphosphazene (P₃N₃, 2) molecule-a key molecular building block in phosphorus chemistry-has remained elusive. Here, we report a facile, versatile pathway producing cyclotriphosphazene and its Dewar benzene-type isomer (P₃N₃, 5) in ammonia-phosphine ices at 5 K exposed to ionizing radiation. Both isomers were detected in the gas phase upon sublimation via photoionization reflectron time-of-flight mass spectrometry and discriminated via isomer-selective photochemistry. Our findings provide a fundamental framework to explore the preparation of inorganic, isovalent species of benzene (C₆H₆) by formally replacing the C─H moieties alternatingly through phosphorus and nitrogen atoms, thus advancing our perception of the chemical bonding of phosphorus systems.

SUBMITTER: Zhu C

PROVIDER: S-EPMC7439403 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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The elusive cyclotriphosphazene molecule and its Dewar benzene-type valence isomer (P3N3).

Zhu Cheng C Eckhardt André K AK Bergantini Alexandre A Singh Santosh K SK Schreiner Peter R PR Kaiser Ralf I RI

Science advances 20200722 30

Although the chemistry of phosphorus and nitrogen has fascinated chemists for more than 350 years, the Hückel aromatic cyclotriphosphazene (P3N3, 2) molecule-a key molecular building block in phosphorus chemistry-has remained elusive. Here, we report a facile, versatile pathway producing cyclotriphosphazene and its Dewar benzene-type isomer (P3N3, 5) in ammonia-phosphine ices at 5 K exposed to ionizing radiation. Both isomers were detecte ...[more]

PMID: 32832667

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