Chalcogen-Bonded Cocrystals of Substituted Pyridine N-Oxides and Chalcogenodiazoles: An X-ray Diffraction and Solid-State NMR Investigation was written by Xu, Yijue;Kumar, Vijith;Bradshaw, Maressa J. Z.;Bryce, David L.. And the article was included in Crystal Growth & Design in 2020.Application of 3718-65-8 This article mentions the following:
Me, MeO, and Ph substituents are introduced at the para-, meta-, and ortho- positions of pyridine N-oxide to study the effect of chem. substitution on the resulting 9 chalcogen-bonded structures formed upon cocrystn. with 3,4-dicyano-1,2,5-selenodiazole and 3,4-dicyano-1,2,5-telluradiazole. Single-crystal x-ray diffraction studies reveal double chalcogen bonding interactions in the cocrystals and demonstrate the impact of the substitution on the geometric features of the chalcogen bonds. 77Se and 125Te solid-state NMR spectroscopy is employed to measure Se and Te chem. shift tensors of the products, and various trends are described. The smallest component of the 77Se chem. shift tensor (δ33) provides the strongest correlation with the chalcogen bond distance. Solution NMR provides qual. evidence for the persistence of the chalcogen bonds in solution 1J(77Se,14N) coupling constants in 3,4-dicyano-1,2,5-selenodiazole and its chalcogen-bonded cocrystals are measured after accounting for residual dipolar coupling between 77Se and 14N; however, changes in 1J(77Se,14N) attributable to chalcogen bonding upon cocrystn. are comparable to the exptl. uncertainties. This systematic study of chalcogen-bonded cocrystals demonstrates the potential utility of the substitution effect for applications of chalcogen bonds in crystal engineering and demonstrates the value of solid-state NMR in characterizing such systems. Chalcogen-bonded cocrystals based on 3,4-dicyano-1,2,5-selenodiazole and 3,4-dicyano-1,2,5-telluradiazole are reported. Various substituted pyridine N-oxides act as electron donors. X-ray diffraction and 77Se/125Te solid-state NMR are employed to characterize these novel materials. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Application of 3718-65-8).
3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Application of 3718-65-8