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 環(huán)氧化合物在HF/Pyridine，Bu₄NH₂F₃，Et₃N.3HF，Me₃N.2HF，SiF₄，DAST等親核試劑作用下開(kāi)環(huán)，生成鄰位氟代的醇。

HF/Pyridine在溫和的條件下高產(chǎn)率的使環(huán)氧開(kāi)環(huán)，有些底物的區(qū)域選擇性和立體選擇性也不錯(cuò)。

【Ayi, A, I;Remli, M; Guedj, R. Tetrahedron. Lett. 1981, 22, 1505】

SiF₄是更溫和的一個(gè)試劑，很多官能團(tuán)如雙鍵，醚鍵，C-Si鍵在這個(gè)條件下也不會(huì)斷裂。

【Begum, C, G; Charlon, C; Coulombeau, C; Luu, D, C. J.Fluorine. Chem. 1976, 8, 531.】

【 Kanemoto, S; Shimizu,M; Yoshioka, H. Tetrahedron. Lett. 1987, 28, 6313.】

反應(yīng)實(shí)例

The mixture of epoxide (1.56 g, 10 mmol) and Me₃N.2HF(1.48 g, 15 mmol) in CH₂Cl₂(50 mL) was heated to reflux for 2 hours. The resulting mixture was extracted with CH₂Cl₂and washed with aq. K₂CO₃ solution and brine, the organicphase was dried over Na₂SO₄ and the solvent was removedunder reduced pressure.  The residue waspurified by column chromatography on silica gel to give the desired product (1.1 g, 63%).

【Amri, H; El Gaied, M, M. J.Fluorine. Chem. 1990, 46, 75.】 

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