Cl[C:2]1[C:11]([Cl:12])=[N:10][C:9]2[C:4](=[CH:5][CH:6]=[C:7]([N+:13]([O-:15])=[O:14])[CH:8]=2)[N:3]=1.[F:16][C:17]([F:27])([F:26])[CH:18]([C:20]1[CH:21]=[N:22][CH:23]=[CH:24][CH:25]=1)[OH:19].[H-].[Na+].[Cl-].[NH4+]>C1COCC1>[Cl:12][C:11]1[C:2]([O:19][CH:18]([C:20]2[CH:21]=[N:22][CH:23]=[CH:24][CH:25]=2)[C:17]([F:16])([F:26])[F:27])=[N:3][C:4]2[C:9]([N:10]=1)=[CH:8][C:7]([N+:13]([O-:15])=[O:14])=[CH:6][CH:5]=2In THF (200 mL) was dissolved 2,3-dichloro-6-nitroquinoxaline (4.00 g, 16.4 mmol) and the mixture was cooled to −78° C. To the solution were added 2,2,2-trifluoro-1-(pyridin-3-yl)ethanol (3.05 g, 17.2 mmol) obtained in Step 1 and sodium hydride (1.31 g, 32.8 mmol) and the mixture was stirred at −78° C. allowing the temperature to rise slowly to −30° C. over 1 hour. A saturated aqueous ammonium chloride solution was added to the reaction mixture. Extraction with ethyl acetate, washing with saturated brine and drying over anhydrous magnesium sulfate were performed. After filtration, the solvent in the filtrate was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=1/0 to 3/2) to give 3-chloro-6-nitro-2-(2,2,2-trifluoro-1-(pyridin-3-yl)ethoxy) quinoxaline (3.98 g, 63% yield).
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