Potassium Carbonate → 2-[3-nitro-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl]-4-(trifluoromethyl)phenol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 4-bromo-3-nitro-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole (Preparation 869, 18.95 g, 0.06864 mol) in 1,2-dimethoxyethane (175 mL) was added aqueous potassium carbonate (2M in water, 68.0 mL, 0.123 mol) and tetrakis(triphenylphosphine)palladium(0) (6.34 g, 0.00549 mol). The reaction was sparged 3 times with Argon and heated to 75° C. To this, [2-hydroxy-5-(trifluoromethyl)phenyl]boronic acid (Preparation 871, 21.22 g, 0.103 mol) was added in four portions over six hours. The reaction solution was heated for an additional 12 hours and then allowed to cool. The mixture was diluted with ethyl acetate, washed with water and brine, dried over anhydrous magnesium sulfate, filtered, and concentrated. Purification by automated flash column chromatography using a 0-50% ethyl acetate/hexanes gradient and a 80 g column gave the title compound (13.2 g, 54%) as a yellow oil.

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