Ammonium Hydroxide → HCID 89781995、化合物

To a solution of 5-bromo-2,3-dichloroquinoxaline (Leadgen Labs, Orange, Conn.; 2.00 g, 7.20 mmol) in 50 mL DMF at 0° C. was added NH4OH (30% NH3 in water; 18.68 ml, 144 mmol) dropwise via syringe. A thick solid formed. 2 mL DMF was added to promote stirring. The thick reaction was sealed and stirred for 2 h at RT. The reaction was diluted with 250 mL water and let stand overnight. In the morning, it was filtered and the solid was air dried, treated with silica gel and DCM, and concentrated in vacuo. The material was purified by silica gel chromatography using 0-50% EtOAc/hexane to separately provide 5-bromo-3-chloroquinoxalin-2-amine (0.510 g, 1.973 mmol, 27% yield) as a peach-colored solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 7.69-7.76 (1H, m), 7.43-7.61 (4H, m). m/z (ESI, +ve) 259.9 (M+H)+ and 8-bromo-3-chloroquinoxalin-2-amine (0.78 g, 3.02 mmol, 42% yield) as a solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 7.94 (1H, dd, J=7.6, 1.4 Hz), 7.73-7.79 (1H, m), 7.61 (2H, br. s.), 7.30 (1H, t, J=7.9 Hz). m/z (ESI, +ve) 259.9 (M+H)+.