[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6](O)=[O:7])=[C:4]([NH:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:3]=1.Cl.[CH3:19][NH:20][O:21][CH3:22].C(N(CC)C(C)C)(C)C.CCCCCC>CN(C=O)C.C(OCC)(=O)C>[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([N:20]([O:21][CH3:22])[CH3:19])=[O:7])=[C:4]([NH:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:3]=1To a solution of 4-chloro-2-phenylamino-benzoic acid (10.1 g, 41.0 mmol) in DMF (200 mL) was added O-benzotriazole-N,N,N′,N′-tetramethyl-uronium-hexafluorophosphate (HBTU, 31.2 g, 82.0 mmol), N,O-dimethyl-hydroxylamine hydrochloride (7.94 g, 82.0 mmol), and N,N-diisopropylethylamine (45.0 g, 350.0 mmol) at room temperature. The resulting mixture was stirred for 24 hr. at room temperature. Completion of the reaction was confirmed by silica TLC (mobile phase; hexane:ethyl acetate=7:3; Rf=0.5). The reaction mixture was diluted with ethyl acetate (600 mL) and the organic layer was washed with water (4×200 mL) and brine (200 mL). The organic layer was dried over anhydrous Na2SO4 and volatiles were removed under reduced pressure. The crude material was purified over silica gel (100-200 mesh) column chromatography, using gradient polarity mobile phase (ethyl acetate:hexane=1:9-1:4), to give 4-chloro-N-methoxy-N-methyl-2-phenylamino-benzamide (6.62 g, 56.4% yield) as a yellow solid. 1H NMR (DMSO-d6) δ ppm 7.93 (s, 1H) 7.20-7.39 (m, 3H) 7.02-7.17 (m, 3H) 6.88-6.99 (m, 2H) 3.50 (s, 3H) 3.20 (s, 3H). MS calcd. for C15H15ClN2O2 [(M+H)+] 291.0, obsd. 291.0, [(M-C2H6NO)+] 230.0, obsd. 230.0.
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