BrCC1C(Cl)=C(Cl)C=C2C=1N=C(OC)C(OC)=N2.[Cl:19][C:20]1[CH:25]=[C:24]([Cl:26])[C:23]([Cl:27])=[CH:22][C:21]=1[N+:28]([O-:30])=[O:29].Cl[CH2:32][C:33]([O:35][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:34].CC(C)([O-])C.[K+].Cl>O1CCCC1>[N+:28]([C:21]1[C:20]([Cl:19])=[CH:25][C:24]([Cl:26])=[C:23]([Cl:27])[C:22]=1[CH2:32][C:33]([O:35][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:34])([O-:30])=[O:29]Preparation 1: 5-Bromomethyl-6,7-dichloro-2,3-dimethoxyquinoxaline (a) A solution of 2,4,5-trichloronitrobenzene (103 g, 0.46 mol) and t-butyl chloroacetate (79 mL, 0.55 mol) in dry tetrahydrofuran (400 mL) was added dropwise over 30 minutes to a solution of potassium t-butoxide (128 g, 1.14 mol) in dry tetrahydrofuran (800 mL) with stirring, under nitrogen keeping the temperature at -40° C. After the addition was complete, the resulting dark blue solution was stirred for a further 30 minutes. The mixture was poured into 0.5M hydrochloric acid (2 L) and the product was extracted into ethyl acetate (2.5 L and 1 L). The combined organic solutions were dried (MgSO4) and evaporated onto silica gel (70-200μ, 200 g). The silica gel was applied to the top of a silica gel chromatography column (800 g), and the product was eluted using a hexane/ethyl acetate gradient. Product-containing fractions were combined and evaporated to give a yellow solid, which was triturated with hexane to give t-butyl (2-nitro-3,5,6-trichlorophenyl)acetate (91.8 g, 59%) as a white solid. Found C, 42.32; H, 3.50; N, 4.03. C12H12Cl3 NO4 requires C, 42.32; H, 3.55, N, 4.11%.
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