Toluene → 5-(4-Cyano-phenyl)-6-(2,2,2-trifluoro-ethoxy)-nicotinic acid methyl ester

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Reaction Conditions

Reaction Steps

In a 50 mL 4-necked flask, methyl 5-bromo-6-(2,2,2-trifluoroethoxy)nicotinate (1 g, 3.18 mmol, Eq: 1.00, CAN 1211589-51-3) and cesium carbonate (3.11 g, 9.55 mmol, Eq: 3) were combined with toluene (25 ml) and water (2.8 ml) to give a colorless solution. The reaction mixture was 3× degassed and purged with argon; then palladium(II) acetate (14.3 mg, 63.7 μmol, Eq: 0.02), potassium (4-cyanophenyl)trifluoroborate (732 mg, 3.5 mmol, Eq: 1.1, CAN 850623-36-8) and butyldi-1-adamantylphosphine (68.5 mg, 191 μmol, Eq: 0.06) were successively added. The degassing-purging cycle was repeated after each addition. The reaction mixture was then heated to 120° C. for 5 hours. After cooling, the reaction mixture was poured into 50 mL H2O and extracted with AcOEt (2×50 mL). The organic layers were washed with H2O/NaCl solution, combined, dried over Na2SO4 and concentrated in vacuo. Purification by flash chromatography (silica gel, 50 g, 50% to 100% CH2Cl2 in heptane) yielded finally 898 mg of the title compound as white foam; MS (EI) 337.2 (M+H)+.

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