[C:1](Cl)(=[O:5])[CH2:2][CH2:3][CH3:4].[CH3:7][NH:8][C:9]1[CH:14]=[CH:13][C:12]([N+:15]([O-:17])=[O:16])=[CH:11][CH:10]=1.C(N(CC)CC)C>C(Cl)(Cl)Cl>[CH3:7][N:8]([C:9]1[CH:10]=[CH:11][C:12]([N+:15]([O-:17])=[O:16])=[CH:13][CH:14]=1)[C:1](=[O:5])[CH2:2][CH2:3][CH3:4]To a stirred solution of butyryl chloride (0.770 g, 7.23 mmol) in chloroform ( 15 mL) was added N-methyl-4-nitroaniline and triethylamine (1.2 mL, 8.6 mmol). After overnight stirring, additional butyryl chloride (0.40 mL, 3.9 mmol) was added and the reaction was refluxed for 2-3 hours. The reaction was concentrated and the residue partitioned between ethyl acetate and aqueous sodium bicarbonate solution. The organic layer was combined with a second ethyl acetate extract, dried (sodium sulfate) and concentrated. The resulting dirty yellow oil was purified by flash chromatography over silica (methylene chloride/methanol) to afford 1.11 g (76%) of product as a pale yellow solid: 1H NMR (CDCl3) δ 8.30 (d, J=8.9 Hz, 1H), 7.40 (d, J=8.9 Hz, 1H), 3.34 (s, 3H), 2.18 (t, J=7.5 Hz, 2H), 1.71-1.59 (m, 2H), 0.88 (t, J=7.6Hz,
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