4-Iodo-2-(trifluoromethyl)pyridine → [5-ethoxy-2-(4-fluorophenyl)-2H-1,2,3-triazol-4-yl][2-(trifluoromethyl)-4-pyridinyl]methanone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of isopropylmagnesium chloride lithium chloride complex (1.3 M in THF, 8.5 mL, 11.0 mmol) was added to a solution of 4-iodo-2-(trifluoromethyl)pyridine (3.0 g, 11.0 mmol) in tetrahydrofuran (10 mL) cooled to 0° C. After 10 minutes, the solution was stirred at 23° C. for 35 min. The dark reddish brown solution was then cooled to −78° C. A solution of 5-ethoxy-2-(4-fluorophenyl)-N-methoxy-N-methyl-2H-1,2,3-triazole-4-carboxamide (i.e. the product of Step B, 2.5 g, 8.5 mmol) in tetrahydrofuran (25 mL) was added. The solution was stirred at 23° C. for 22 h. The reaction was quenched by the addition of a saturated aqueous ammonium chloride solution (10 mL) and water (10 mL). The mixture was extracted with ethyl acetate (2×40 mL), dried (MgSO4) and concentrated under reduced pressure to obtain the crude product. The crude residue was purified by chromatography on silica gel eluting with 0 to 20% ethyl acetate in hexanes to afford the title compound (1.8 g) as a colorless solid.

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