Synthesis
8-Amino-6-methoxyquinoline can be obtained by reducing 6-methoxy-8-nitroquinoline with iron powder in hydrochloric acid medium and then neutralizing it with liquid base. The steps are as follows:
Put hydrochloric acid into a glass-lined reaction pot, raise the temperature to 50C, put in 6-methoxy-8-nitroquinoline and iron powder. At 65-70 in 3.5h all added, holding 2h, cooling, filtration of crude 8-amino-6-methoxyquinoline hydrochloride. Then it was refined by salting out, neutralized to pH 7 with dilute base, precipitated 8-amino-6-methoxyquinoline, filtered to get the crude product, and refined with toluene to get the final product.
Purification Methods
Distil it under N2 and at high vacuum, then recrystallise it several times from MeOH (0.4mL/g). It remains colourless for several months when purified in this way [Elderfield & Rubin J Am Chem Soc 75 2963 1953]. The hydrobromide [312693-53-1] M 255.1 has m 238o(dec). [Beilstein 22 III/IV 5934.]