硝化反應

原標題：硝化反應

舊文重發，溫故知新

一、芳香族硝化反應

10、硼酸被硝基取代生成硝基化合物反應示例

芳基硼酸用NH4NO3/(CF3CO)2O，NH4NO3/TMSCl 或MNO3/TMSCl （M＝Ag，Na，K）處理，發生硼被硝基取代的反應，生成硝基化合物。前一個條件比較強，後兩個條件相對溫和，反應在室溫下進行，收率高，這是最近報導的一種方法，應用面還不太廣。

To the mixture of silver nitrate (374 mg, 2.2 mmol) in DCM (10 mL) was added TMSCl (238 mg, 2.2 mmol),the mixture was stirred for 15 min, followed by the addition of 3-chlorophenylboronicacid (156 mg, 1mmol). The resultingmixture was stirred at rt for 72 h, then filtered, the filtrate was washed withNaHCO3solution, extracted with DCM. The solvent was removed under reduced pressure, the residue was purifiedby column chromatography to give the desired compound (140 mg, 90%).

【Prakash, G. K. S;Panja, C; Mathew, T; Olah, G. A. Org. Lett, 2004, 2205】

11、苯胺氧化生成硝基化合物反應示例

將苯胺用如過酸、臭氧、Oxone，雙氧水等氧化劑處理，則生成相應的硝基化合物，這也是合成芳香族硝基化合物的一種方法。

A 300-mL three-necked flask equipped with a Trubore stirrer, dropping funnel,and reflux condenser protected with a calcium chloride drying tube is charged with 100 mL of methylene chloride.To this solvent is added without stirring 90% hydrogen peroxide (5.4 mL, 0.20 mol)of. The hydrogen peroxide is not misciblewith the solvent and separates as the lower layer at the bottom of the flask.The flask is then cooled in an ice bath, and thestirrer is started. To this cold solution over a 20-minute period is added (34.0 mL0.24 mol) of trifluoroacetic anhydride. After addition is complete, the ice bath isremoved and the solution is stirred at room temperature for 30 minutes.

Asolution is then prepared from (8.1 g, 0.05 mole) of 2,6-dichloroanilineand 80 mL of methylenechloride. This solution is added dropwise over a 30-minute period to thepreviously prepared peroxytrifluoroacetic acidreagent. During this addition the exothermic reaction causes the mixture toreflux. After addition is complete, the mixture is heated under reflux for 1hour. It is then cooled and poured into cold water (150 mL). The organic layer is separated, washed with water(100 mL), with 10% sodiumcarbonate solution (2 x 100-mL), and finallywith water (50 mL). The organic extract is treated with activated charcoal andanhydrous magnesium sulfate. After standingovernight, the volatile solvent is removed at aspirator pressure with the aidof a warm water bath. There is obtained (8.6–8.8 g, 89–92%)of yellow 2,6-dichloronitrobenzene, mp 63–68°C.The product is recrystallized from a minimum volume (12–15mL) of ethanol and washed on the filter with10 mL of cold ethanolto give a slightly off-white product (5.7–7.0 g59–73%),mp 69–70°C

【Organic Syntheses, Coll. Vol. 5, p.367; Vol. 49, p.47.】

二、脂肪族硝化反應

脂肪族硝基化合物的合成

Henry反應

硝基烷烴對α，β-不飽和羰基化合物進行製備硝基化合物。

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