Sodium hydride → 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid [2-methoxy-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-yl]-amide

Beteiligte Stoffe

Reaktionsschritte

A solution of 2-methoxy-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-ylamine (162 mg, 0.517 mmol, prepared as described in Example 5, Step B above) in THF (10 mL) was treated with NaH (62.1 mg, 1.55 mmol, 60% dispersion in oil) at room temperature, and the mixture was allowed to stir for 1 h. Simultaneously, a solution of 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid (168 mg, 0.776 mmol, prepared as described in Example B above) in anhydrous DCM (10 mL) was treated with oxalyl chloride (67.7 μL, 0.776 mmol) and DMF (2 drops), and the mixture was stirred at room temperature for 1 h. Volatile components were removed in vacuo, and the residue was taken up in anhydrous THF (6 mL). The above-prepared acid chloride solution was added to the sodium anilide solution above, and the mixture was stirred at room temperature for 1 h. The mixture was quenched with saturated aqueous NH4Cl (20 mL) and extracted twice with EtOAc (25 mL). The residue was purified on a 12-g SEPRA Si 50 SPE column (Flow rate=15 mL/min; Eluent=EtOAc-hexanes, 1:99 for 10 min, then 1:99 to 3:17 over 40 min) to yield 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid [2-methoxy-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-yl]-amide as a white solid. Mass Spectrum (LCMS, APCI pos.): Calculated for C22H21N5O4ClF3: 512.1 (M+H). Measured: 512.1.

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