Action of pyridine N-oxide and of the picoline N-oxides on 2-bromopyridine. Oxidative brominations with pyridine N-oxide hydrobromide was written by Ramirez, Fausto;Von Ostwalden, P.. And the article was included in Chemistry & Industry (London, United Kingdom) in 1957.SDS of cas: 13472-81-6 This article mentions the following:
2-BrC5H4N (I) and pyridine 1-oxide (II) at 100鎺?give, after a 2-hr. induction period, C5H5N, N-(2-pyridyl)-2-pyridone (III), and the 3-Br derivative (IV) of III, m. 129鎺?(obtained but not identified by Takeda, et al., C.A. 47, 8071a). The presence of HBr eliminates the induction period and also leads to the formation of addnl. products, such as the 3,5-di-Br derivative (V) of III, m. 158鎺? and 2,5-dibromo-2-pyridone, m. 207鎺? IV and V are formed from III by oxidative bromination. A mixture of III and the HBr salt of II gives at 200鎺?IV, C5H5N, and some V. With PhMe as moderator and HBr as initiator, I + II give little or no brominated products. Similarly, 3-picoline N-oxide yields the N-(5-methyl-2-pyridyl) analog of III, m. 94鎺? and of IV, m. 152鎺? 4-picoline N-oxide gives the N-(4-methyl-2-pyridyl) analog of III, m. 114鎺? 2-picoline N-oxide, the N-(6-methyl-2-pyridyl) analog, m. 42鎺? Thus a heterocyclic N-oxide can act both as reagent and subsequently as substrate in nucleophilic attacks. The position of Br in IV was proved by bromination of III with 1 mole Br to IV, and comparison with authentic 5-Br derivative of III (m. 134鎺? synthesized from 5-bromo-2-pyridone and I. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6SDS of cas: 13472-81-6).
3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) 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. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. SDS of cas: 13472-81-6