Cesium carbonate → 4-[2-Chloro-5-(trifluoromethyl)phenyl]pyridazine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

[2-Chloro-5-(trifluoromethyl)phenyl]boronic acid (0.410 g, 1.83 mmol), caesium carbonate (1.1 g, 3.38 mmol) and 4-bromopyridazine hydrobromide (Preparation 20, 0.35 g, 1.46 mmol) were dissolved in 1,4-dioxane (3.5 mL) and water (1 mL). The mixture was heated to 80° C. under nitrogen then palladium tetrakis triphenylphosphine (0.085 g, 0.074 mmol) was added. The reaction was stirred for three hours before it was left to cool to room temperature. The mixture was subsequently filtered through Arbocel®, then diluted in ethyl acetate (15 mL) and washed twice with a saturated solution of aqueous brine (15 mL). The organic layer was collected, dried over sodium sulphate, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography (ISCO™, 0-50% ethyl acetate in heptane gradient elution, 12 g SiO2) to give title compound as a green solid (0.23 g, 61%).

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