Sodium hydride → 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid [2-(4-methyl-piperazin-1-yl)-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-yl]-amide

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Reaction Steps

A solution of 2-(4-methyl-piperazin-1-yl)-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-ylamine (240 mg, 0.630 mmol, prepared as described in the previous step) in THF (10 mL) was treated with NaH (75.6 mg, 1.89 mmol, 60% dispersion in mineral oil) at room temperature for 1 h. At the same time, a solution of 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid (164 mg, 0.756 mmol, prepared as described in Example B) in DCM (10 mL) was treated with oxalyl chloride (66.0 μL, 0.756 mmol) and DMF (2 drops) at room temperature for 1 h. The resulting mixture was concentrated in vacuo, taken up in THF (6 mL), and added to the sodium anilide solution at room temperature. The solution was stirred at room temperature for 30 min, quenched with saturated aqueous NH4Cl (20 mL), and extracted three times with EtOAc (25 mL). The combined extracts were dried over MgSO4 and concentrated in vacuo. The residue was purified on a 24-g SEPRA Si 50 SPE column (Isco system: Flow rate=15 mL/min; Eluent=EtOAc-hexanes, 3:2 v/v for 5 min, then 3:2 to 4:1 v/v over 40 min) to yield 5-tert-butyl-4-chloro-2-methyl-2H-pyrazole-3-carboxylic acid [2-(4-methyl-piperazin-1-yl)-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-yl]-amide as an orange solid. Mass Spectrum (LCMS, APCI pos.): Calculated for C26H29ClF3N7O3: 580.2 (M+H). Measured: 580.2.

Provenance & Evidence