Acetyl chloride → Methyl 5-bromo-2-(methylsulfanyl)pyrimidine-4-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Acetyl chloride (6.26 ml, 0.088 mol) was added dropwise at 0-5° C. to methanol (100 ml). The mixture was stirred at 0-5° C. for 5 min. 5-Bromo-2-methylsulfanylpyrimidine-4-carboxylic acid (20 g, 0.08 mol) was added in portions at 0-5° C. then the mixture was heated under reflux for 1 h, during which time the slurry dissolved, then it was cooled to ambient temperature and poured into saturated aqueous sodium hydrogencarbonate solution (100 ml). The product was extracted into dichloromethane (3×100 ml), the extracts were washed with water (100 ml), dried (MgSO4) and evaporated in vacuo. The residual solid was crystallised from hexane to give 5-bromo-2-methylsulfanylpyrimidine-4-carboxylic acid methyl ester (12.27 g) as an off white crystalline solid, m.pt. 67-70° C.; 250 MHz 1H-NMR (CDCl3) δ (ppm): 2.6 (s, 3H) (—SCH3), 4.05 (s, 3H) (—OCH3), 8.7 (s, 1H) (ArH); m/z (M+H)+. 249; HPLC purity 96%; HPLC retention time 1.58 min.

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