Reference of 918321-20-7, These common heterocyclic compound, 918321-20-7, name is Methyl 5-amino-4-fluoro-1-methyl-1H-benzo[d]imidazole-6-carboxylate, 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.
In an inertized (N2) reaction vessel at internal temperature 20C and under exclusion of humidity and air, Compound 1 (1.0 eq.) and Compound 2 (1.2 eq.) are reacted in the presence of cesium carbonate (2.4 eq.), tris(dibenzylidenaceton) dipalladium(O) (0.035 eq.) and Xantphos (0.07 eq.) in a mixture of toluene and 1 ,4-dioxane at internal temperature of 99C. After 8 hours, the mixture is cooled to internal temperature of 60C. Subsequently, dimethylformamide (DMF), filter aid (CEFOK) and activated charcoal (EKNS) are added, and the mixture is stirred and cooled to internal temperature of 35 C. The solids are filtered off and washed with a mixture of dimethylformamide and toluene. To the filtrate, which contains the product Compound 3, is introduced at internal temperature of25 C hydrogen chloride gas (CLC) whereupon the HQ salt of Compound 3 crystallizes. The palladium residue mainly remains in solution. After warming to 60 C and cooling to 0C, the solids are filtered using a centrifuge and are washed with a mixture of toluene and dimethylformamide. The damp Compound 3 HC1 salt is charged to a reactor (equipped with pH probe) together with dimethylformamide and is heated to 60C. By adding a 4 wt% of aqueous tripotassium phosphate solution, the pH is adjusted to a pH range of 6.8-7.6 (with a target of pH 7.2) while Compound 3 crystallizes as free base. After cooling to 22C and stirring, the solids are filtered using a centrifuge and are washed with drinking water. The moist solids are dried at 50 C under vacuum to give dry, crude Compound 3. In order to remove residual palladium, dry, crude Compound 3 is dissolved in dimethylformamide at internal temperature of 60C and stirred together with Smopex-234 (commercially available from Johnson Matthey) and activated charcoal for 90 minutes. The solids are filtered off at internal temperature of 60C and are washed with dimethylformamide. To the filtrate are added drinking water and Compound 3 seed crystals. More drinking water is added while Compound 3 crystallizes. After cooling to internal temperature of 20 C, the solids are filtered using a centrifuge and are washed with a mixture of deionized water and dimethylformamide and with deionized water. The moist solids are dried at 50C under vacuum, providing 6-(4-Bromo-2-fluorophenylamino)-7-fluoro-3- methyl-3H-benzoimidazole-5-carboxylic acid methyl ester (Compound 3).
The synthetic route of 918321-20-7 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; NOVARTIS AG; ARRAY BIOPHARMA INC.; KRELL, Christoph, Max; MISUN, Marian; NIEDERER, Daniel, Andreas; PACHINGER, Werner, Heinz; WOLF, Marie-christine; ZIMMERMANN, Daniel; LIU, Weidong; STENGEL, Peter, J.; NICHOLS, Paul; WO2014/63024; (2014); A1;,
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