Conformational Dynamics of a Bispyridinium Cyclophane

• Published in: Journal of organic chemistry Vol. 68; no. 22; pp. 8697 - 8699
• Main Authors: Conejo-García, Ana, Campos, Joaquín M, Entrena, Antonio, Sánchez-Martín, Rosario M, Gallo, Miguel Á, Espinosa, Antonio
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 31.10.2003
• Subjects: Chemistry; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with several n hetero atoms in the same ring, in separated rings or in fused rings; Organic chemistry; Preparations and properties; Hydrogen 1; Molecular rotation; Chemical shift; Pyridinium compounds; Nitrogen heterocycle; Conformational dynamics; NMR spectrometry; Cyclophane; High temperature; Conformational equilibrium; Low temperature
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo0301292

A complete study of the conformational behavior of 4,8-diaza-3(1,4),9(4,1)-dipyridina-1,6(1,4)-dibenzenacyclodecaphan-31,91-bis(ilium) bishexafluorophosphate is described. This study allows us to conclude that the process observed by which the different chemical shifts of the pyridinium protons show coalescence at a high-temperature 1H NMR is the rotation around the C−N bond, whereas the conformational equilibrium between the four conformers is produced at low temperature.