With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.1834-27-1,6-Chloro-4-methylpyridazin-3(2H)-one,as a common compound, the synthetic route is as follows.
A solution of 6-chloro-4-methylpyridazin-3-ol (Intermediate X17; 0.50 g, 3.4 mmol) in DCM (20 mL) was treated with (5-(methoxycarbonyl)-2-methylphenyl)boronic acid (1.0 g, 5.2 mmol), Cu(OAc)2 (1.2 g, 6.9 mmol), pyridine 1-oxide (327 mg, 3.44 mmol) and pyridine (1.1 g, 14 mmol). The resulting mixture was stirred at ambient temperature open to the atmosphere for one overnight. The reaction mixture was diluted with DCM (100 mL) and washed with water (2 x 30 mL). The organic extracts were dried over anhydrous Na2SO4(), filtered and concentrated under vacuum. The crude residue was purified by silica gel flash chromatography (2-55% EtOAc/hexane as the gradient eluent) to afford the title compound (2.99 g, 99% yield). MS (apci) m/z = 293.0 (M+H), 295.0 [(M+H)+2] (with Cl pattern)., 1834-27-1
As the paragraph descriping shows that 1834-27-1 is playing an increasingly important role.
Reference：
Patent; ARRAY BIOPHARMA, INC.; ANDREWS, Steven W.; BLAKE, James F.; COOK, Adam; GUNAWARDANA, Indrani W.; HUNT, Kevin W.; METCALF, Andrew T.; MORENO, David; REN, Li; TANG, Tony P.; (263 pag.)WO2017/70708; (2017); A1;,
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