反应详情

温度

-40 °C

To 4-(trifluoromethyl)benzo[c][1,2]oxaborol-1(3H)-ol (CXXX) (1.17 g, 5.79 mmol) cooled to −40° C. was slowly added HNO3 (10 mL, 99%). The reaction mixture was stirred for 3 h at −40° C. and then slowly quenched with crushed ice. The yellow precipitate was filtered and washed with hexane to produce 6-nitro-4-(trifluoromethyl)benzo[c][1,2]oxaborol-1(3H)-ol (CXXXI) as a yellow crystalline solid (950 mg, 3.83 mmol, 66% yield). ESIMS found for C8H5BF3NO4 m/z 246.4 (M−H).

1. customslowly quenched with crushed ice
2. filtrationThe yellow precipitate was filtered
3. washwashed with hexane