September 29, 2021 News Introduction of a new synthetic route about 1003-21-0

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference of 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 5.5h 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 (2 x 100 mL) then dried over MgSO4 and concentrated in vacuo. Purification of the residue on silica gel afforded (1-methyl-1H-imidazol-5-yl)(2-thienyl)methanone [10.2 g, yield 36% ; HPLC/MS : m/z = 193 (M+H) ; logP(HcooH) = 0.52].

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

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