170232-68-5

General procedure for the synthesis of 2,4-dibromothiazole-5-carboxaldehyde from 2,4-dibromothiazole-5-methanol: 2,4-dibromothiazole-5-carboxaldehyde (2.0 g, 7.4 mmol) was dissolved in methanol (80 mL) and NaBH4 (419 mg, 11.0 mmol) was added. The reaction mixture was stirred at room temperature overnight. Upon completion of the reaction, the reaction was quenched with 10% NaOH solution, diluted with water and extracted with ethyl acetate (2 times). The organic phases were combined and concentrated under reduced pressure to remove the solvent. The resulting crude product was purified by silica gel column chromatography with hexane/ethyl acetate (3:1, v/v) as eluent to give 2,4-dibromothiazole-5-methanol (1.84 g, 91% yield). Mass spectrum (DCI/NH3) showed m/z 274 (M+). 1H NMR (500 MHz, CDCl3) δ 2.11 (s, 1H), 4.78 (s, 2H).

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