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ChemicalBook CAS DataBase List 3,6-Dihydroxy-4,5-dimethylpyridazine
5754-17-6

3,6-Dihydroxy-4,5-dimethylpyridazine synthesis

3synthesis methods
4.png
Hydrazine hydrochloride (58 g, 552 mmol) is dissolved in hot water (300 mL) and dimethyl maleic anhydride (58 g, 460 mmol) is added in portions and the suspension stirred at reflux for 16 h. The suspension is cooled down to room temperature and the precipitate is filtered, washed with water and dried at 40° C. under vacuum to yield 4,5-dimethyl-1,2-dihydro-pyridazine-3,6-dione (36) (64 g, 99%).
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Yield:5754-17-6 99%

Reaction Conditions:

with hydrazine hydro-chloride in water;Reflux;

Steps:

4,5-Dimethyl-1,2-dihydro-pyridazine-3,6-dione (compound 36)

Hydrazine hydrochloride (58 g, 552 mmol) is dissolved in hot water (300 mL) and dimethyl maleic anhydride (58 g, 460 mmol) is added in portions and the suspension stirred at reflux for 16 h. The suspension is cooled down to room temperature and the precipitate is filtered, washed with water and dried at 40° C. under vacuum to yield 4,5-dimethyl-1,2-dihydro-pyridazine-3,6-dione (36) (64 g, 99%).1H-NMR (400 MHz, DMSO-d6) δ=11 (br s, 2H), 2.01 (s, 6H).MS (m/z, MH+) meas. 141.1.

References:

US2010/41663,2010,A1 Location in patent:Page/Page column 41

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