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Updated: Sep 10, 2025

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes
Published on: August 5, 2016
Unraveling Addition, Cyclization, and Dehydrogenation Reactions between Pyridinyl Radicals and Acrylonitrile Using
Yuxin Liu1, Jiao Gao2, Chengcheng Wei1
1MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510631, P. R. China.
Abstract:
In this study, we tackle the challenge of synthesizing nitrogen-containing bicyclic compounds in the gas phase, a topic of considerable interest to interstellar chemistry and combustion science. We specifically explore the bimolecular reaction between the o-pyridinyl radical (C5H4N•), a quintessential nitrogen-containing monocyclic carbon-centered aromatic radical, and the interstellar molecule acrylonitrile (C3H3N) in a resistance-heated silicon carbide (SiC) microreactor. Utilizing advanced molecular beam-sampled synchrotron VUV photoionization mass spectrometry (SVUV-PIMS), we detected the formation of C8H6N2 species at 1100 K. Photoionization efficiency (PIE) curve analysis suggested the exclusive production of a ring-tail structure, rather than the desired bicyclic 1,5-naphthyridine structure. High-level ab initio calculations revealed a detailed reaction mechanism that addition, cyclization, and subsequent dehydrogenation reactions between C5H4N• and C3H3N can lead to the formation of either 3-(2-pyridinyl)-2-propenenitrile or 1,5-naphthyridine. However, the formation of 1,5-naphthyridine under the present experimental conditions was not efficient, as supported by rate coefficient calculations. The complex mechanisms of radical-neutral reactions were revealed in this work, guiding the gas-phase synthesis of nitrogen-containing aromatic compounds.
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