反应详情

Combine in a 500 mL schlenk flask, 2-nitro-benzo[b]thiophene-3-carbonitrile (5.8 g, 28.4 mmol) and Pd/C (3.0 g, 10% w/w, 2.84 mmol) in 1,2-dichloroethane (120 ml), the reaction mixture is charged with a balloon of hydrogen. After overnight stirring, release the hydrogen, remove the catalyst by filtration, and wash the catalyst by 1,2-dichloroethane several times. Concentrate down to a residue, which purified by flash chromatography on silica gel, gradient (100% hexane to 100% of Hexane:CH2Cl2:EtOAc=50:50:2.5), afford brownish solid 3.6 g of title compound (yield 73%). Mass spectrum: ES(+)(m/e): 175 (M+1); 1H NMR (300MHz, DMSO-d6, ppm): δ 7.81 (br, 2H), 7.65–7.62 (m, 1H), 7.28–7.24 (m, 2H), 7.11–7.01 (m, 1 H).

1. customremove the catalyst
2. filtrationby filtration
3. washwash the catalyst by 1,2-dichloroethane several times
4. concentrationConcentrate down to a residue, which
5. custompurified by flash chromatography on silica gel, gradient (100% hexane to 100% of Hexane:CH2Cl2:EtOAc=50:50:2.5)