4-BroMopyridazine HydrobroMide

4-Bromopyridazine Hydrobromide is a mono-substituted pyridazine derivative used in the preparation of γ-secretase modulators.

As a mono-substituted pyridazine derivative, 4-Bromo-pyridazine hydrobromide can be used in the preparation of γ-secretase modulators.

4-Bromopyridazine is synthesized from 3,6-dichloropyridazine in four steps. 1) 3,6-Dichloropyridazine reacts with chlorine at 100C to give 3,4,6-trichloropyridazine. 2) 3,4,6-Trichloropyridazine is refluxed with 15% NaOH solution. After acidification and recrystallization, 3,6-dichloro-4-hydroxypyridazine is obtained. 3) 3,6-Dichloro-4-hydroxypyridazine is subjected to pressurized hydrogenation in methanol in an autoclave using Pd/C as catalyst. Work-up yields 4-hydroxypyridazine. 4) 4-Hydroxypyridazine reacts with phosphorus tribromide oxide. After pH adjustment with ammonia, chloroform extraction, column chromatography, and recrystallization, 4-bromopyridazine is obtained.