1093106-54-7

5-Acetyl-2-amino-4-methylthiazole (200 mg, 1.26 mmol) was used as starting material and suspended in acetonitrile (ACN, 15 mL). Copper bromide (286 mg, 1.0 eq.) and isoamyl nitrite (511 μL, 3.0 eq.) were added sequentially. The reaction mixture was heated to reflux for 3 hours. After completion of the reaction, the reaction solution was diluted with dichloromethane (DCM) and washed sequentially with saturated brine and ethylenediaminetetraacetic acid (EDTA) solution. The organic phase was dried with anhydrous magnesium sulfate (MgSO4) and concentrated under reduced pressure to remove the solvent. Purification by silica gel column chromatography (eluent: dichloromethane) afforded 263 mg of the target compound 1-(2-bromo-4-methylthiazol-5-yl)ethanone in 94% yield as a yellow oil. The structure of the product was confirmed by 1H NMR (75 MHz, CDCl3): δ 2.71 (3H, s, 4-CH3), 2.51 (3H, s, 6-CH3), which is consistent with literature data (PCT Int. Appl., 2010128163). High-resolution mass spectrometry (HRMS-ESI) analysis showed that the calculated value of [MNa+] was 219.94262 and the measured value was 219.24264.

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