用硫酸或甲酸作溶劑，用氮?dú)庀♂尩?/span>F2能直接對苯環(huán)發(fā)生親電取代，生成氟代苯，不過由于用到F2，其操作不方便。
前面列出的大多數(shù)試劑，都能對活化的芳環(huán)發(fā)生親電取代，得到相應(yīng)的氟化合物。如下所示，但反應(yīng)的選擇性不是很好，產(chǎn)物主要是鄰對位取代的混合物：
反應(yīng)實(shí)例
To the solutionof phenol (0.94 g,10 mmol) in dry CH2Cl2 (20 mL) was addedN-fluoropyridinium salt (2.54 g,10 mmol), the mixture was stirred under reflux for 24 h. The reaction was monitored by TLC. Then 20 mL of water was added to the reactionmixture, the resulting mixture was extracted with CH2Cl2,the organic phase was dried over Na2SO4, the solvent wasevaporated under reduced pressure, the residue was purified by flash column chromatography on silica gel to give themixture of two ismers (1.05 g, 94%, o:p = 84: 10) as a colorless oil.
【Umemoto, T; Fukami, S. J. Am. Chem Soc. 1990, 112, 8563】
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