Discovery of 1003-21-0

1003-21-0, A common heterocyclic compound, 1003-21-0, name is 5-Bromo-1-methyl-1H-imidazole, molecular formula is C4H5BrN2, its 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.

To a solution of 5-Bromo-1-methyl-imidazole (18.8 g, 117 mmol) in dichloromethane (50 mL) was added dropwise ethylmagnesium bromide (3 M in Et2O, 38.9 mL, 117 mmol). After stirring at room temperature for 30 min, the reaction mixture was cooled down to 0C with an ice-brine bath and N-methoxy-N-methylthiophene-3-carboxamide (20.0 g, 117 mmol) was added dropwise. The mixture was stirred for 3.5h at room temperature. The mixture was worked-up by addition of water (400 ml_), then acidified with aq. HCI (1 M) until pH = 7. After extraction with dichloromethane (3 x 100 ml_), the organic layers were washed with water (100 ml_) then dried over MgSO4 and concentrated in vacuo. Purification of the residue on silica gel afforded (1- methyl-1H-imidazol-5-yl)(3-thienyl)methanone [11.6 g, yield 41% ; HPLC/MS : m/z = 193 (M+H) ; logP(HcooH) = 0.43].

The synthetic route of 1003-21-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER CROPSCIENCE SA; WO2009/130193; (2009); A1;,
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem