日韩不卡在线观看视频不卡,国产亚洲人成A在线V网站,处破女八a片60钟粉嫩,日日噜噜夜夜狠狠va视频

網(wǎng)站首頁/有機(jī)反應(yīng)/烯烴的制備/羰基烯醇醚化反應(yīng)制備烯基醚
羰基烯醇醚化反應(yīng)制備烯基醚

烯基醚的合成基本上可以參考烯烴和醚這兩種官能團(tuán)的合成方法。


羰基烯醇醚化反應(yīng)制備烯基醚


羰基化合物與其烯醇式是互變異構(gòu)體,使用合適的基團(tuán)使得烯醇式的羥基醚化,即可制得烯基醚化合物。


實例一

To a mixture of S6 (140 mg, 0.285mmol) and tert-butyldimethylsilyl chloride (TBSCl, 86.0 mg, 0.570 mmol)in THF (5.7 mL) was added dropwise potassium bis(trimethylsilyl)amide (KHMDS,0.5 M solution in toluene, 2.0 mL) at –78 °C, and the resulting mixture was stirred for 3 h. The reaction was quenched with saturated aqueous ammonium chloride. The mixture was extracted with ethyl acetate and the combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo. Purification of the residue by flash column chromatography using diol silica gel (DIOL MB 100-40/75) with ethyl acetate/n-hexane(1:4) afforded (148 mg, 86%) as a colorless oil.

Reference: Org. Lett. 201416, 768-771.


實例二

In a 50 mL round bottomed flask methyl acetoacetonate (20.0 g,172 mmol, 1.0 eq), trimethylorthoformate (18.6 g, 175 mmol, 1.0 eq) and concentrated H2SO4 (6 drops) were added and stirred at 20°C for 24 h. After this time, a slight excess of quinoline (12 drops) was added to neutralize the acid. Distillation under reduced pressure afforded the(E)-methyl-3- methoxybut-2-enoate 15a. Colourless liquid, yield (19.5 g, 149mmol,87% yield).

Reference: J.Am.Chem.Soc. 2012134, 19362-19365


來源:覽博網(wǎng)



納孚服務(wù)
  • 化學(xué)試劑
  • 提供稀有化學(xué)試劑現(xiàn)貨

  • 化學(xué)試劑定制合成服務(wù)
  • 上海納孚生物科技有限公司提供市場稀缺的化學(xué)試劑定制服務(wù)

  • 新材料現(xiàn)貨
  • 上海納孚生物科技有限公司代理或自產(chǎn)包含石墨烯產(chǎn)品,類石墨烯產(chǎn)品、碳納米管、無機(jī)納米材料以及一些高分子聚合物材料

  • 結(jié)構(gòu)設(shè)計及定制合成
  • 可以根據(jù)客戶需求對所需化合物結(jié)構(gòu)進(jìn)行設(shè)計改性,從而定制合成出客戶所需分子式結(jié)構(gòu)

  • 聯(lián)系我們
  • 021-58952328
  • 13125124762
  • info@chemhui.com
  • 關(guān)注我們
在線客服
live chat