[Cl:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[CH:5][C:6]([F:12])=[CH:7][CH:8]=2)[N:3]=1.[Li]CCCC.CON(C)[C:21](=[O:23])[CH3:22]>C1COCC1>[Cl:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[C:5]([C:21](=[O:23])[CH3:22])[C:6]([F:12])=[CH:7][CH:8]=2)[N:3]=1To a solution of 2-chloro-7-fluoroquinoline (ECA International Corp, Palatine, Ill.; 300 mg, 1.652 mmol) in THF (5.0 mL) at −78° C. was added nBuLi, 1.6 M in hexanes (1.24 mL, 1.98 mmol) slowly dropwise. The solution was stirred at −78° C. for 30 min. A solution of N-methoxy-N-methylacetamide (0.25 mL, 2.48 mmol) in THF (0.5 mL) was added slowly dropwise via syringe. After 10 min, the reaction was warmed to RT. After 15 min, the reaction was quenched by addition of saturated aq. NH4Cl. The reaction was partitioned between saturated NH4Cl and EtOAc. The organic layer was washed with brine, dried over MgSO4, filtered and concentrated. The crude material was purified by silica gel chromatography, using 0-50% EtOAc/hexane. The pure fractions were combined and concentrated in vacuo to give 1-(2-chloro-7-fluoroquinolin-8-yl)ethanone (56 mg, 0.250 mmol, 15.16% yield): 1H NMR (400 MHz, DMSO-d6) δ ppm 8.57 (d, J=8.6 Hz, 1H), 8.25 (dd, J=9.1, 6.2 Hz, 1H), 7.65-7.74 (m, 2H), 2.68 (s, 3H). m/z (ESI, +ve ion) 224.0 (M+H)+.
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