Evans, Richard Castleman et al. published their research in Journal of the American Chemical Society in 1945 | CAS: 19064-65-4

3-Methoxypyridazine (cas: 19064-65-4) belongs to pyridazine derivatives. Pyridazines are rare in nature, possibly reflecting the scarcity of naturally occurring hydrazines, common building blocks for the synthesis of these heterocycles. Pyridazine is bioavailable (especially in the CNS) and can reduce toxicity. Pyridazine is a component of several drug molecules, and the pyridazine pharmacophore has contributed to a variety of pharmacologically active compounds.COA of Formula: C5H6N2O

Pyridazine series. Absorption spectrum of pyridazine was written by Evans, Richard Castleman;Wiselogle, F. Y.. And the article was included in Journal of the American Chemical Society in 1945.COA of Formula: C5H6N2O This article mentions the following:

α-Oxoglutaric acid (380 g.) in 600 cc. hot H2O, added to 230 g. tech. NaOH and 340 g. N2H4.H2SO4 in 1.5 l. H2O, gives 50% of 1,4,5,6-tetrahydro-6-oxo-3-pyridazinecarboxylic acid (I), m. 195-6°; dehydrogenation of 284 g. of I in 1 l. boiling AcOH with 360 g. tech. Br (several drops per sec.) gives 65% of 1,6-dihydro-6-oxo-3-pyridazinecarboxylic acid (II), m. 257° (decomposition). Decarboxylation of I by melting gives 23% of 4,5-dihydro-3(2)-pyridazone, m. 41-3°; II gives 90% of 3(2)-pyridazone (III), b1 146-8°, m. 102°. III (30 g.), treated with 50 cc. POCl3 and stirred 45 min. at 65-75°, gives 68% of 3-chloropyridazine (IV), which decomposes rapidly at 95°/1 mm.; solutions of IV in EtOH appear to be relatively stable at room temperature IV (24 g.) in 20 cc. concentrated NH4OH and 50 cc. 95% EtOH and 0.75 g. Pd on Norite A, hydrogenated at room temperature and 45 lb. pressure for 15-30 min., give 5.2 g. pyridazine (V), b1 47-8°, b. 205-6°, d2020 1.111, nD30 1.5148. The ultraviolet absorption curves are given for V in hexane and H2O and for its HCl salt in H2O. III (15 g.) and 10 g. Me2SO4 in 50 cc. MeOH, treated with 8 g. NaOH and refluxed 1 hr., give 2 g. of the 2-Me derivative (VI), hygroscopic, m. 38-9°. IV (12 g.) and MeONa in MeOH give 6 g. of 3-methoxypyridazine (VII), b5 77-8°, nD30 1.5086; 3-EtO analog, b2-3 69-71°, m. 35-6°, nD30 1.5000, 56% yield. VI is thermally stable but VII slowly decomposes at room temperature In the experiment, the researchers used many compounds, for example, 3-Methoxypyridazine (cas: 19064-65-4COA of Formula: C5H6N2O).

3-Methoxypyridazine (cas: 19064-65-4) belongs to pyridazine derivatives. Pyridazines are rare in nature, possibly reflecting the scarcity of naturally occurring hydrazines, common building blocks for the synthesis of these heterocycles. Pyridazine is bioavailable (especially in the CNS) and can reduce toxicity. Pyridazine is a component of several drug molecules, and the pyridazine pharmacophore has contributed to a variety of pharmacologically active compounds.COA of Formula: C5H6N2O

Referemce:
Pyridazine – Wikipedia,
Pyridazine | C4H4N2 – PubChem