Infrared absorption band due to nitrile stretching vibration of cyanopyridine derivatives was written by Tani, Hideo;Fukushima, Kunio. And the article was included in Yakugaku Zasshi in 1961.Electric Literature of C7H6N2 This article mentions the following:
Infrared spectra of NCC5H4N derivatives having various substituents were examined The CN stretching absorption of the CN bonded directly to the ring appears at 2239 ± 4 cm.-1, while that of cyanomethylpyridine derivatives appears at 2257 ± 4 cm.-1 Introduction of an electron-attracting group into the ring shifts the CN stretching absorption to a higher wave-number region, with marked decrease in its intensity. The absorption band splits into two 2- and 3-NCC5H4N(O), appearing, resp., at 2237 and 2245 cm.-1, and at 2241 and 2249 cm.-1 The CN stretching absorption in 4-NCC5H4N(O) derivatives shifts to a lower wave number than those of 4-NCC5H4N derivatives, with marked increase in their intensity. The relation between Hammet’s σ value and wave number, mol. extinction coefficient, and integrated absorption intensity is generally linear. The wave number and intensity of CN stretching absorption in 2-and 4-NCC5H4N(O) are markedly different from those of 2- and 4-NCC5H4N, indicating that the electron-donating property of the NO bond in 4-NCC5H4N(O) is considerable. This is also suggested by the result of nitration of C5H5N(O). In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Electric Literature of C7H6N2).
4-Methylpicolinonitrile (cas: 1620-76-4) 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. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Electric Literature of C7H6N2