Vinylnitrene (H2C=CH–N) is an unstable species that has so far not been directly identified by spectroscopic methods. Its significant 1,3-diradical character gives this compound a tendency for structural rearrangement or fragmentation. Vinylphosphinidene and vinylarsinidene (latter pictured) are higher congeners of vinylnitrene and have also not been identified until now.
Artur Mardyukov, University of Gießen, Germany, and colleagues have synthesized the parent triplet vinylarsinidene via the low-temperature photolysis of diazidovinylarsine at 10 K in an argon matrix, resulting in the elimination of three nitrogen molecules. The team found that vinylarsinidene can also be generated via high-vacuum flash pyrolysis of diazidovinylarsine at 700 °C, followed by trapping with an excess of argon at 10 K.
The researchers used matrix-isolated infrared (IR) and UV/Vis spectroscopy as well as computational methods to study the compound’s formation and reactivity. They found that vinylarsinidene can be transformed into vinylidenearsane, triplet ethynylarsinidene, 2H-arsirene, or a complex of arsinidene (HAs) and acetylene. The team proposes that vinylphosphinidene could behave similarly to vinylarsinidene and might also be observable under low-temperature conditions.
- Preparation and Photochemistry of Parent Triplet Vinylarsinidene,
Weiyu Qian, Peter R. Schreiner, Artur Mardyukov,
J. Am. Chem. Soc. 2023.