2,4-Dichloropyridine → 4-chloro-N-(2-methylpyrazol-3-yl)pyridin-2-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM(0) (50.1 mg, 0.05 mmol) was added in one portion to 2,4-dichloropyridine (200 mg, 1.35 mmol), 1-methyl-1H-pyrazol-5-amine (144 mg, 1.49 mmol), cesium carbonate (660 mg, 2.03 mmol) and (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (93 mg, 0.16 mmol) in 1,4-dioxane (20 mL) warmed to 105°C over a period of 24 hours under nitrogen. The reaction mixture was evaporated to dryness and redissolved in DCM (20 mL), and washed with water (25 mL). The organic layer filtered using phase separating paper and evaporated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 0 to 3% MeOH in DCM. Pure fractions were evaporated to dryness to afford 4-chloro-N-(1-methyl-1H-pyrazol-5-yl)pyridin-2-amine (171 mg, 60.5 %) as a yellow crystalline solid.

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