Infrared spectra of heterocyclic compounds. III. Infrared spectra of alkylpyridine 1-oxides was written by Shindo, Hideyo. And the article was included in Pharmaceutical Bulletin in 1956.Application In Synthesis of 3,5-Dimethylpyridine 1-oxide This article mentions the following:
Infrared absorption spectra were measured (curves shown) for pyridine 1-oxide (I), its 2-, 3-, and 4-Me derivatives, its 2,3-, 2,4-, 2,6-, and 3,5-di-Me (II) derivatives, its 2,3,4-, 2,3,6- (III), 2,4,5-, and 2,4,6-tri-Me derivatives, its 2,3,4,6-tetra-Me and 2,3,4,5,6-penta-Me derivatives, and its 3- and 4-Et derivatives All the compounds were prepared by well-known methods and were distilled in vacuo immediately before measuring. Only II and III were new, picrates, m. 138-9° and 102°, resp. By comparing these spectra with those previously reported (C.A. 51, 5557b) for the corresponding alkylpyridines (IV), the characteristic absorption band for the N-oxide group was established as between 1200 and 1300 cm.-1 (cf. Costa and Blasina, C.A. 49, 8702i). This conclusion is discussed on the basis of the facts that (1) I and all its alkyl derivatives show this band with high intensity, (2) only this band shifts to lower frequency with traces of MeOH (because of H bonding), (3) very sensitive relations exist between the frequency of this band and the positions of the alkyl groups, and (4) this absorption region is appropriate to the double-bond nature of the N-H bond. No marked relation was found between the out-of-plane C-H deformation frequencies at 700-900 cm.-1 in these compounds and those in the corresponding IV. The C:C and C:N stretching vibration frequencies at 1450-1650 cm.-1 were quite different from, and often the reverse of, those of the corresponding IV. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Application In Synthesis of 3,5-Dimethylpyridine 1-oxide).
3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Application In Synthesis of 3,5-Dimethylpyridine 1-oxide