The effect of the substituents on the carbonyl absorptions of 2H-pyrid-2-ones and 2H-thiopyran-2-ones was written by Siddiq, Muhammad. And the article was included in Pakistan Journal of Scientific and Industrial Research in 1988.Synthetic Route of C5H3Br2NO This article mentions the following:
The IR spectra of a number of substituted 2H-pyrid-2-ones and 2H-thiopyran-2-ones have been measured in the carbonyl stretching vibration region and interpreted in terms of the chem. effect of the substituents. In general, the presence of electron withdrawing substituents at the 1-, 3-, or 3,5-positions and electron donating substituents at the 1-, 4-, or 5-positions of the 2-pyridone have been found to raise and lower the carbonyl absorption, resp. The substituted 2H-thiopyran-2-ones show an appreciable decrease in their carbonyl absorptions as compared to the corresponding 2-pyridones. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6Synthetic Route of C5H3Br2NO).
3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Synthetic Route of C5H3Br2NO