These common heterocyclic compound, 175137-46-9, name is 5-Cyclopropyl-1H-pyrazol-3-amine, 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. Safety of 5-Cyclopropyl-1H-pyrazol-3-amine
To a mixture of 110a (2.38 g, 7.00 mmol), 5-cyclopropyl-lH-pyrazol-3-amine (905 mg, 7.35 mmol), in 1,4-dioxane (40 mL) in a 100 mL single-neck round-bottomed flask was added cesium carbonate (6.84 g, 21.0 mmol). The mixture was purged with nitrogen for 30min. Tris(dibenzylideneacetone)dipalladium(0) (641 mg, 0.700 mmol) and 4,5- bis(diphenylphosphino)-9,9-dimethylxanthene (688 mg, 1.19 mmol) were then added. The flask was connected to a nitrogen-purged condenser and the mixture was refluxed for 6 h under nitrogen. The mixture was cooled to room temperature and filtered. The filter cake was suspended in ethyl acetate (30 mL) and water (10 mL) and filtered through Celite. The layers were separated. The combined organic layers were dried with anhydrous magnesium sulfate. The drying agent was removed by filtration. The filtrate was concentrated under reduced pressure. The residue was purified on silica eluted with a gradient 0 to 50% ethyl acetate in heptane to afford 6-chloro-4-(5-cyclopropyl-lH-pyrazol-3-ylamino)-2-((2- (trimethylsilyl)ethoxy)methyl)pyridazin-3(2H)-one (111a) (1.58 g, 59%).
The synthetic route of 5-Cyclopropyl-1H-pyrazol-3-amine has been constantly updated, and we look forward to future research findings.