den Hertog, H. J. published the artcileDerivatives of pyridine and quinoline. LXXXIX. Derivatives of pyridine 1-oxide. IV. Directive influence of the 1-oxide group during the nitration of derivatives of pyridine 1-oxide, Computed Properties of 18437-58-6, the publication is Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1951), 591-9, database is CAplus.
3-Ethoxypyridine (I) is converted to 3-ethoxypyridine I-oxide phthalate (II), m. 83.5-4.5°, with o-HO2CC6H4CO3H in Et2O. II with fuming HNO3 and H2SO4 yields 3-ethoxy-4-nitropyridine 1-oxide (III), m. 134-5°, which with Fe powder in HOAc gives 3-ethoxy-4-aminopyridine (picrate, m. 194-5°; mono-Ac derivative, m. 112.5-13.0°). Oxidation and nitration of 2-ethoxypyridine yields g-ethoxy-4-nitropyridine 1-oxide, m. 132.5-3.5°, which was reduced to 4-amino-2-ethoxypyridine, m. 88-9° forms a mono-Ac derivative, m. 105-5.5°, whose picrate m. 161-2°. The mono-Ac derivative of 2-amino-3-ethoxypyridine (IV) is prepared from IV and ketene, while the di-Ac derivative, m. 57.5-8.0°, is obtained from IV with Ac2O at 215°. 2-Bromopyridine on oxidation and nitration yields 2-bromo-4-nitropyridine 1-oxide, m. 145.5-6.0°, reduced to 4-amino-2-bromopyridine, m. 95-7°. 2-Methylpyridine treated as above gives 2-methylpyridine 1-oxide phthalate, m. 115-16°, which on nitration yields 2-methyl-4-nitropyridine 1-oxide, m. 156-6.5°, reduced to 2-methyl-4-aminopyridine, m. 95.5-6°.
Recueil des Travaux Chimiques des Pays-Bas et de la Belgique published new progress about 18437-58-6. 18437-58-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 4-Amino-2-picoline, and the molecular formula is C6H8N2, Computed Properties of 18437-58-6.
Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem