Synthesis of reaction substrates: tert-Butyl 4-bromo-3-nitrophenylcarbamate (1) To a suspension of 4-bromo-3nitroaniline (2.0 g, 9.22 mmol) in MeCN (46 ml) were added Et 3 N (2 ml, 27.6 mmol), DMAP (0.11 g, 0.92 mmol) and di-tert-butyl dicarbonate (3.02 g, 13.8 mmol) sequentially. This solution was then stirred overnight at room temperature. The solution was partitioned between EtOAc (100 ml) and brine (50 ml), and concentrated. The crude mixture was purified using silica column chromatography

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... 10% EtOAc in cyclohexane) to yield the title compound as white needles (1.963 g, 67%). m.p = 119-120°C; R f = 0.32 (10% EtOAc in cyclohexane); 1 H NMR (500MHz, CDCl 3 ) δ 1.53 (9H, s), 6.71 (1H, br s), 7.39 (1H, dd, J = 8.5, 2.5), 7.61 (1H, d, J = 8.5), 8.05 (1H, d, J = 2.5); 13 C NMR (126MHz, CDCl 3 ) δ 28.2, 82.0, 106.6, 115.0, 122.4, 135.1, 138.8, 150.1, 152.0; IR (film) 3337, 1731, 1585, 1394, 1369, 1240, 1155; HRMS (ESI) m/z calcd for C 6 H 4 BrN 2 O 2 [M -Boc] + 214.9456, found [M -Boc + H] + 214.9460; HPLC purity >95%. N-benzyl-4-bromo-3-nitroaniline (4b) Benzaldehyde (0.35 ml, 3.456 mmol) and 4-bromo-3-nitroaniline (0.50 g, 2.304 mmol) were added to a solution of dibutyl tin dichloride (70 mg, 0.2304 mmol) in THF (4.6 ml) at rt in a microwave vial. Phenylsilane (0.44 ml, 4.608 mmol) was added and the vial was capped. The mixture was heated with stirring in a microwave for 7 minutes (2 mins ramp time) at 100 °C. The resultant mixture was cooled and concentrated in vacuo. The residue was purified by silica column chromatography (10-