[C:1]([O-])([O-])=O.[K+].[K+].CI.[Br:9][C:10]1[CH:19]=[CH:18][C:17]([C:20]([OH:22])=[O:21])=[C:16]2[C:11]=1[CH:12]=[CH:13][CH:14]=[N:15]2>CN(C=O)C>[CH3:1][O:21][C:20]([C:17]1[CH:18]=[CH:19][C:10]([Br:9])=[C:11]2[C:16]=1[N:15]=[CH:14][CH:13]=[CH:12]2)=[O:22]K2CO3 (61.3 g, 444.0 mmol) and methyl iodide (63.1 g, 444.0 mmol) were added to a stirred suspension of 5-bromoquinoline-8-carboxylic acid (28.0 g, 111.0 mmol) in DMF (250 mL) at r.t. The reaction mixture was heated at 45° C. for 36 h, cooled to r.t, filtered the solids, washed with ethyl acetate (100 mL). The filtrate was diluted with water, extracted with ethyl acetate (3×300 mL) and washed with water (3×100 mL). The ethyl acetate layer was dried (Na2SO4), filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with ethyl acetate in hexanes (0-20%) to afford methyl-5-bromoquinoline-8-carboxylate as a cream color solid (20.5 g, 70% for 2 steps). 1H NMR (400 MHz, CDCl3) δ 9.07 (dd, J=4.3, 1.5 Hz, 1H), 8.60 (dd, J=8.7, 1.6 Hz, 1H), 7.88 (s, 2H), 7.58 (dd, J=8.6, 4.0 Hz, 1H), 4.05 (s, 3H)
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