EXPLORING THE PROPERTIES AND REACTIVITY OF CARBONYL DIISOTHIOCYANATE WITH ROTATIONAL SPECTROSCOPY

Accessing simple molecules is crucial to our understanding of chemical reactivity. Particularly, characterization of heavier homologues of molecules essential to life, e.g., carbonic acid and urea, can lead to new insights. Synthetic routes to such compounds, followed by exploration of their reactiv...

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Bibliographic Details
Published in:Proceedings of the 2023 International Symposium on Molecular Spectroscopy
Main Author: Gougoula, Eva
Other Authors: Schnell, Melanie, Tambornino, Frank
Format: Conference Object
Language:English
Published: International Symposium on Molecular Spectroscopy 2023
Subjects:
Online Access:https://hdl.handle.net/2142/122380<https://hdl.handle.net/2142/122380>
http://hdl.handle.net/2142/122380
https://doi.org/10.15278/isms.2023.6933
Description
Summary:Accessing simple molecules is crucial to our understanding of chemical reactivity. Particularly, characterization of heavier homologues of molecules essential to life, e.g., carbonic acid and urea, can lead to new insights. Synthetic routes to such compounds, followed by exploration of their reactivity, could not only deepen our knowledge of synthetic chemistry, but also create the basis for novel applications and new research fields. It is known that the reactivity and properties of a compound are a function of its structure. Subsequently, exploring molecular structure in an isolated environment in the absence of lattice and solvent effects is key to our understanding of the structure vs properties relationship. Carbonyl diisothiocyanate (CDIT), C₃N₂O₂S₂, a highly unstable and reactive compound, was first synthesized in 1902.¹ It recently has been characterized in the condensed phase,² however, to the best of our knowledge, this is the first study addressing its properties in the gas phase. The rotational spectra of two isomers of CDIT, syn-syn and syn-anti, were recorded with Chirped Pulse Fourier Transform Microwave (CP-FTMW). Presence of two quadrupolar nuclei (N, I=1) results in hyperfine splitting of rotational transitions, which is analyzed and provides a direct insight into the electronic environment of the molecule. Detection of ¹³C, ³⁴S, ¹⁵N and ¹⁸O isotopologues in their natural isotopic abundances allowed for structure determination of the most abundant syn-syn isomer in the gas phase. The gas phase structure is compared to the previously determined crystal structure and demonstrates a high level of consistency. Spectral analysis is guided by quantum chemical calculations and CDIT, owing to the isothiocyanate substituents, makes an interesting case for theoretical benchmarking.