反应详情

温度

80 °C

m-Phenylenediamine (2.8 mmol, 0.30 g) and 2-fluoro-5-nitropyridine (0.92 mmol, 0.13 g) were dissolved in 6 mL of DMSO. The solution was heated to 80° C. for 18 hours. The solution eventually turned dark red. The reaction mixture was cooled to room temperature and purified directly by flash column chromatography (silica, EtOAc:Hexanes=1:3) to give N1-(5-nitropyridin-2-yl)benzene-1,3-diamine as a reddish crystalline compound (0.19 g, 89% yield): 1H NMR (500 MHz, CDCl3) δ 9.08 (d, 1H, J=2.5 Hz), 8.24 (dd, 1H, J1=2.5 Hz, J2=9.5 Hz), 7.281 (s, 1H), 7.19 (t, 1H, J=8.0 Hz), 6.82 (d, 1H, J=9.5 Hz), 6.74 (s, 1H), 6.70 (d, 1H, J=8.0 Hz), 6.56 (d, 1H, J=7.5 Hz), 3.80 (br, 2H); 13C NMR (125 MHz, CDCl3) δ 159.91, 148.05, 146.93, 139.09, 137.15, 133.59, 130.77, 112.80, 112.66, 109.13, 106.67. The nitro compound (0.43 mmol, 0.10 g) and 10% Pd/C (10 mg) were added to a 20 mL test tube equipped with a stir bar, dry ice (0.5 g) was added to the mixture just before MeOH (7 mL) was added. The suspension was then put into a pressure vessel under 80 psi of H2. The reaction mixture was stirred for 2 hours. The solution turned from yellow to colorless. The reaction mixture was transferred into a 10 mL syringe and filtered through an Acrodisc syringe Filter into a 100 mL round bottom flask containing 37% aqueous HCl (3 mL). The solvent was then evaporated and azeotroped to dryness with toluene and absolute ethanol (3×30 mL of 1:1 mixture). The product was obtained as a grayish yellow powder in quantitative yield. B. Primary Intermediates of Formula (5)

1. temperatureThe reaction mixture was cooled to room temperature
2. custompurified directly by flash column chromatography (silica, EtOAc:Hexanes=1:3)