反应详情

温度

85 °C

To a mixture of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole (2 g, 8.23 mmol, Aldrich) and 3,5-dichloro-1,2,4-thiadiazole (1.27 g, 8.23 mmol, Aldrich) in 1,2-dimethoxy ethane (30 mL)/H2O (10 mL) was added K2CO3 (2.27 g, 16.46 mmol) and Pd(PPh3)4 (0.95 g, 0.82 mmol). N2 gas was purged for 15 min through the mixture. The reaction was heated at reflux at 85° C. for 6 h. The mixture was cooled to RT and quenched with H2O (100 mL) and was extracted with EtOAc (2×100 mL). The organic layer was dried over anhydrous Na2SO4 and concentrated. The residue was purified by silica-gel column chromatography (eluent: 5% EtOAc in petroleum ether) to give 3-chloro-5-(1H-indol-5-yl)-1,2,4-thiadiazole (680 mg, 35.5%) as an off white solid. MS (ESI, pos. ion) m/z: 236 (M+1); 1H-NMR (300 MHz, CDCl3): δ 8.5 (brs, 1H), 8.29 (d, J=0.8 Hz, 1H), 7.78 (dd, J=8.4, 1.8 Hz, 1H), 7.49 (d, J=8.7 Hz, 1H), 7.32-7.31 (m, 1H), 6.67 (t, J=2.1 Hz, 1H).

1. customN2 gas was purged for 15 min through the mixture
2. temperatureThe reaction was heated
3. temperatureThe mixture was cooled to RT
4. customquenched with H2O (100 mL)
5. extractionwas extracted with EtOAc (2×100 mL)
6. dry with materialThe organic layer was dried over anhydrous Na2SO4
7. concentrationconcentrated
8. customThe residue was purified by silica-gel column chromatography (eluent: 5% EtOAc in petroleum ether)