[CH2:1]([O:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[CH2:10][CH3:11])[CH3:2].[N+:12]([O-])([OH:14])=[O:13]>C(OC(=O)C)(=O)C.C(O)(=O)C>[CH2:1]([O:3][C:4]1[CH:9]=[CH:8][C:7]([N+:12]([O-:14])=[O:13])=[CH:6][C:5]=1[CH2:10][CH3:11])[CH3:2]A solution of 1-ethoxy-2-ethyl benzene (3.5 g, Reference Example 51) in acetic anhydride (30 mL) was chilled in an ice-water bath. A solution of nitric acid (1.4 mL of 90%-30% excess) in acetic acid (25 mL) was added dropwise and the mixture was stirred overnight at ambient temperature. The reaction mixture was poured into ice water (300 mL) and the aqueous mixture was extracted with ethyl acetate (2×200 mL). The combined extracts were evaporated and the residue was chromatographed on silica gel (heptane with gradient of 5 to 10% ethyl acetate) to give 1-ethoxy-2-ethyl-4-nitrobenzene (1.4 g) as a clear liquid. LC-MS (Method E) RT=3.75 minutes, 196 (M+H)+. (i) N-(5-Chloro-4-methoxy-2-nitrophenyl)acetamide
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