Some common heterocyclic compound, 24134-09-6, name is 5-Bromo-1,2-dimethyl-1H-imidazole, molecular formula is C5H7BrN2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. category: imidazoles-derivatives
General procedure: To a solution of 2-disubstituted 1-methyl-1H-imidazole 1 (1 mmol) in DMF (5 mL), NBS(169 mg, 0,95 mmol) was added and the resulting reaction mixture was stirred in the dark at room temperature for 3h. Then, Pd(PPh3)2Cl2 (14 mg, 0.02 mmol, 2 mol%), CuI (8 mg, 0.04mmol, 4 mol%), an alkyne 3 (1,1 mmol) and piperidine (300 muL, 255 mg, 3 mmol) were added and the resulting reaction mixture was stirred at 80C (when trimethylsilylacetylene was employed as the alkyne, the reaction was carried out at 50C) for 3 h. The reaction mixture was diluted with EtOAc (100 mL), then saturated aqueous NH4Cl (100 mL) was added. The resulting mixture was stirred for 30 minutes and extracted with EtOAc (3x 25mL). The organic extracts were washed with water (3 x 25 mL) and brine (1 x 25 mL), driedover anhydrous Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by flash chromatogaraphy on silica gel. This procedure was employed to prepare compounds 4a-l. GLC analysis showed that all these compounds had chemical purity higherthan 98%.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 24134-09-6, its application will become more common.