To a 250 mL round bottom flask was added 2,4-dichlorobenzene-1-carbothioamide (4.0 g, 19 mmol, CAS 2775-38-4), ethyl 3-bromo-2-oxopropionate (10.0 g, 51 mmol), ethanol (20 mL) and pyridine (4.8 g, 61 mmol). The reaction mixture was stirred at 80 °C overnight. After completion of the reaction, the mixture was cooled to room temperature and concentrated under reduced pressure. The residue was purified by silica gel column chromatography with ethyl acetate/petroleum ether (1:5) as eluent to afford ethyl 2-(2,4-dichlorophenyl)-1,3-thiazole-4-carboxylate (2.0 g, 31% yield) as a yellow solid.LC-MS: m/z = 302.0 [M + H]+, tR = 1.3 min. 1H NMR (300 MHz, CDCl3) δ 8.32 (s, 1H), 7.54 (d, J = 2.1 Hz, 1H), 7.39 (dd, J = 8.6, 2.1 Hz, 1H), 4.48 (q, J = 7.1 Hz, 2H), 1.45 (t, J = 7.1 Hz, 3H).
