反应详情

温度

-78 °C

In an oven-dried flask, 4-nitro-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole (412.4 mg, 1.695 mmol) was dissolved in 5 mL THF and cooled at −78° C. To this solution was slowly added 1.0M Lithium hexamethyldisilazide in tetrahydrofuran (2.0 mL, 2.0 mmol). After stirring for 30 minutes at −78° C., a solution of hexachloroethane (455.2 mg, 1.923 mmol) in 3 mL THF was slowly added. The reaction mixture was kept at −78° C. for an additional hour, and then quenched with saturated aqueous ammonium chloride and warmed to room temperature. The reaction mixture was partitioned between ethyl acetate and water, and the organic layer dried over magnesium sulfate and evaporated in vacuo to yield 0.4592 g (98%) of 5-chloro-4-nitro-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole, which was carried forward without further purification. LCMS (ESI) m+H=220.2; 1H NMR (400 MHz, DMSO-d6) δ: 8.52 (s, 1H), 5.56 (s, 2H), 3.67-3.57 (m, 2H), 0.91-0.83 (m, 2H), −0.04 (s, 9H).

1. waitThe reaction mixture was kept at −78° C. for an additional hour
2. customquenched with saturated aqueous ammonium chloride
3. temperaturewarmed to room temperature
4. customThe reaction mixture was partitioned between ethyl acetate and water
5. dry with materialthe organic layer dried over magnesium sulfate
6. customevaporated in vacuo