[F:1][C:2]([F:18])([F:17])[C:3]1[C:12]2[C:7](=[CH:8][CH:9]=[C:10]([N+:13]([O-])=O)[CH:11]=2)[NH:6][C:5](=[O:16])[CH:4]=1.[F-].[Cs+].I[CH:22]([CH3:24])[CH3:23]>CN(C=O)C>[NH2:13][C:10]1[CH:11]=[C:12]2[C:7](=[CH:8][CH:9]=1)[N:6]=[C:5]([O:16][CH:22]([CH3:24])[CH3:23])[CH:4]=[C:3]2[C:2]([F:18])([F:17])[F:1]In a 250-mL r.b. flask, a solution of 4-trifluoromethyl-6-nitroquinolinone (structure 1 of Scheme I) (3.78 g, 14.6 mmol) in DMF (75 mL) was treated with CsF (12.41 g, 73 mmol, 5.0 equiv.) and 2-iodopropane (11.09 g, 73 mmol, 5.0 equiv). The reaction mixture was stirred at room temperature (rt) for 18 h. The reaction mixture was quenched with H2O (100 mL) and extracted with EtOAc (3×200 mL). The combined EtOAc extracts were washed with saturated aqueous NH4Cl solution (300 mL), H2O (300 mL) and brine (300 mL). Dried (MgSO4), filtered and concentrated in vacuo. The residue was purified by flash column chromatography (SiO2, 5×20 cm, 2% EtOAc in hexane as eluent) to afford 3.94 g (90%) of the 2-isopropoxyquinoline as a white solid. Rf 0.81 (SiO2, 10% EtOAc-hexane). 1H NMR (400 MHz, CDCl3) 8.93 (s, 1H), 8.47 (dd, 1H, J=9.2, 2.5), 7.98 (d, 1H, J=9.2), 7.32 (s, 1H), 5.62 (septet, 1H, J=6.2), 1.45 (d, 1H, J=6.2).
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