Conformational properties of ethyl- and 2,2,2-trifluoroethyl thionitrites, (CX3CH2SNO, X = H and F)

The simple 2,2,2-trifluoroethyl thionitrite molecule, CF3CH2SNO, has been prepared in good yield for the first time using CF3CH2SH and NOCl in slight excess. The vapor pressure of the red-brown compound CF3CH2SNO follows, in the temperature range between 226 and 268 K, the equation log p = 12.0-3881...

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Detalles Bibliográficos
Autores: Canneva, Antonela, Della Védova, Carlos Omar, Mitzel, Norbert W., Erben, Mauricio Federico
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/93253
Acceso en línea:http://hdl.handle.net/11336/93253
Access Level:acceso abierto
Palabra clave:S-nitrosothiol
Conformational analysis
IR Spectroscopy
Vibrational properties
Molecular structure
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:The simple 2,2,2-trifluoroethyl thionitrite molecule, CF3CH2SNO, has been prepared in good yield for the first time using CF3CH2SH and NOCl in slight excess. The vapor pressure of the red-brown compound CF3CH2SNO follows, in the temperature range between 226 and 268 K, the equation log p = 12.0-3881/T (p/bar, T/K), and its extrapolated boiling point reaches 51 °C. Its structural and conformational properties have been compared with the ethyl thionitrite analogue, CH3CH2SNO. The FTIR spectra of the vapor of both thionitrites show the presence of bands with well-defined contours, allowing for a detailed conformational analysis and vibrational assignment on the basis of a normal coordinate analysis. The conformational space of both thionitrite derivatives has also been studied by using the DFT and MP2(full) level of theory with extended basis sets [6-311+G(2df) and cc-pVTZ]. The overall evaluation of the experimental and theoretical results suggests the existence of a mixture of two conformers at room temperature. The relative abundance of the most stable syn form (N=O double bond syn with respect to the C-S single bond) has been estimated to be ca. 79 and 75% for CF3CH2SNO and CH3CH2SNO, respectively.