反应详情

温度

50 °C

To a solution of impure 2-amino-7-bromo-6-fluorobenzothiazole from Step A in THF (10 mL) was added tert-butyl nitrite (90%, 1.25 mL, 9.46 mmol). The mixture was stirred at 50° C. for 7 h and then purified by ISCO chromatography (0 to 40% EtOAc:heptane) to afford 114 mg (34%) of the title compound as a yellow solid. 1H NMR (400 MHz, CDCl3): δ 7.54 (dd, J=2.4, 8.0 Hz, 1H), 7.62 (dd, J=2.4, 8.0 Hz, 1H), 9.03 (s, 1H); 19F NMR (376 MHz, CDCl3): δ−113.77; MS (ESI): 231.92/233.92 [M+H]+; HPLC tR=1.38 min (TOF: polar—3 min).

1. custompurified by ISCO chromatography (0 to 40% EtOAc:heptane)