[C:1]([O:5][C:6](=[O:20])[N:7]([CH2:9][C:10]1[C:15]([N+:16]([O-])=O)=[CH:14][CH:13]=[CH:12][C:11]=1[Br:19])[CH3:8])([CH3:4])([CH3:3])[CH3:2].NN>C1COCC1.CO>[C:1]([O:5][C:6](=[O:20])[N:7]([CH2:9][C:10]1[C:11]([Br:19])=[CH:12][CH:13]=[CH:14][C:15]=1[NH2:16])[CH3:8])([CH3:4])([CH3:2])[CH3:3]To a warm solution of (2-bromo-6-nitro-benzyl)-methyl-carbamic acid tert-butyl ester from Preparation 2 (589 mg, 1.71 mmol), and a small (catalytic) amount of Ra(Ni) in THF/MeOH (8 ml/9 ml) was added H2NNH2 (110 μl, 3.5 mmol). With stirring, the solution was heated under reflux for an hour and was allowed to cool to room temperature. The reaction mixture was filtered through celite and washed with ethyl acetate. The concentrated filtrate was purified by flash chromatography to give (2-amino-6-bromo-benzyl)-methyl-carbamic acid tert-butyl ester (371 mg, 69%). 1H NMR (CDCl3, 300 MHz) δ:1.48(s, 9H), 2.80(s, 3H), 4.67(s, 2H), 6.56(m, 1H), 6.90(m, 2H).
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