[N+:1]([C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[CH:10]=[C:11]([N+]([O-])=O)[CH3:12])([O-:3])=[O:2].C1CCN2C(=NCCC2)CC1.[N+:27]([CH2:29][C:30]([O:32][CH2:33][CH3:34])=[O:31])#[C-:28].Cl>C1COCC1.C(O)(C)(C)C.CCOC(C)=O>[CH3:12][C:11]1[C:10]([C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[N+:1]([O-:3])=[O:2])=[C:29]([C:30]([O:32][CH2:33][CH3:34])=[O:31])[NH:27][CH:28]=1
A solution of 1-nitro-2-[2-nitroprop-1-en-1-yl]benzene (4.1 g, 19.7 mmol) in a mixture of THF (131 mL) and tert-BuOH (66 mL) was treated with DBU (4.45 mL, 29.5 mmol) and ethyl isocyanoacetate (2.67 g, 2.58 mL) added. The resulting solution was stirred for 1 h, then heated to 70° C. for 4 h. The mixture was cooled and concentrated in vacuo to give residue that was taken up in EtOAc and aqueous HCl (1 N). The organic layer was separated and washed with brine, then dried over Na2SO4. Filtration and solvent removal afforded a residue that was purified on silica gel (gradient elution, 0-40% EtOAc/hexanes) to afford the title compound (3.2 g, 59%) as solid. LCMS (ES+) m/z 275 (M+H)+.
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