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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM(0) (251 mg, 0.27 mmol) was [AP-added] to 2,4-dichloropyridine (1000mg, 6.76 mmol), 1-methyl-1H-pyrazol-5-amine (722 mg, 7.43 mmol), cesium carbonate (3302 mg, 10.14 mmol) and (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (461 mg, 0.80 mmol) in 1,4-dioxane (75 mL) warmed to 105ºC over a period of 21 hours under nitrogen. The reaction mixture was evaporated to dryness and redissolved in DCM (50 mL), and sequentially with water (25 mL). The organic layer was 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 (710 mg, 50.4 %) as a brown oil.

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