den Hertog, H. J.; de Bruyn, J. published the artcile< Derivatives of pyridine and quinoline. LXXXVIII. Reactions of bromo derivatives of 2- and 3-ethoxypyridines when heated with hydrochloric acid>, Safety of 6-Chloropyridin-2-ol, the main research area is .
Following abstract When a bromoethoxypyridine (0.01 mole in 30-40 ml. 25% aqueous HCl) in a sealed tube is heated 4 hrs. at 160° in a shaking furnace, the Br is replaced by Cl when the former is in the 2- or 6-position, and the EtO group is replaced by the OH group. Thus 6-bromo-2-ethoxypyridine (I) gives 6-chloro-2-hydroxypyridine (II), m. 128.5-9°, and 2-bromo-3-ethoxypyridine (III) gives 2-chloro-3-hydroxypyridine, m. 169-70°, plus the corresponding dihydroxypyridines. The 3,5-di-Cl derivative of I yields 3,5,6-trichloro-2-hydroxypyridine, m. 174-5°. When the Br is in the 3- or 5-position it is not substituted by the procedure given. Thus 5-bromo-3-ethoxypyridine yields 5-bromo-3-hydroxypyridine. But either 3- or 5-bromo-2-ethoxypyridine yields mixtures of 3,5-dibromo-2-hydroxypyridine and 2-hydroxypyridine. As a further example of the positional reactivity of the Br, 2,5,6-tri-bromo-3-ethoxypyridine, m. 86-7°, prepared by heating 3-bromo-5-ethoxypyridine with Br in a sealed tube at 100°, gave 5-bromo-2,6-dichloro-3-ethoxypyridine, m. 77-8° with aqueous HCl. The EtO group in this case remained intact.
Recueil des Travaux Chimiques des Pays-Bas et de la Belgique published new progress about Chlorination. 73018-09-4 belongs to class pyridine-derivatives, and the molecular formula is C5H4ClNO, Safety of 6-Chloropyridin-2-ol.