Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 13808-64-5, name is 4-Bromo-3-methylpyrazole, This compound has unique chemical properties. The synthetic route is as follows., Formula: C4H5BrN2
Example 12 Synthesis of 2-[4-[[4-(ethylamino)-5-(trifluoromethyl)pyrimidin-2-yl]amino]-3-methylpyrazol-1-yl]-2-methylcyclopentanone (194) 2-(4-bromo-3-methylpyrazol-1-yl)cyclopentanone and 2-(4-bromo-5-methylpyrazol-1-yl)cyclopentanone: To a solution of 4-bromo-3-methyl-1H-pyrazole (10 g, 62.11 mmol) in DMF (60 mL) was added NaH (3.23 g, 80.75 mmol, 60% purity) at 0 C. and stirred at 15 C. for 1 h. Then 2-chlorocyclopentanone (8.84 g, 74.53 mmol, 7.43 mL) was added to the mixture and stirred at 15 C. for 15 h. The reaction mixture was quenched by addition aq. NH4Cl (300 mL) at 0 C., and then extracted with EtOAc (3*100 mL). The combined organic layers were washed with brine (200 mL), dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (PE:MTBE=2:1 to 1:1) to give the mixture of 2-(4-bromo-3-methylpyrazol-1-yl)cyclopentanone and 2-(4-bromo-5-methylpyrazol-1-yl)cyclopentanone as a yellow gum. LCMS: RT 2.119 min, m/z=243.1 [M+H]+.
Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 13808-64-5.