Taillefer Marc, Ouali Armelle, Renard Brice, Spindler Jean-Francis
CNRS UMR 5076, Hétérochimie moléculaire et macromoléculaire Ecole Nationale Supérieure de Chimie de Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier Cedex 5, France.
Chemistry. 2006 Jul 5;12(20):5301-13. doi: 10.1002/chem.200501411.
An efficient and straightforward copper-catalyzed method allowing vinylation of N- or O-nucleophiles with di- or trisubstituted vinyl bromides is reported. The procedure is applicable to a broad range of substrates since N-vinylation of mono-, di-, and triazoles as well as O-vinylation of phenol derivatives can be performed with catalytic amounts of copper iodide and inexpensive nitrogen ligands 3 or 8. In the case of more hindered vinyl bromides, the use of the original bidentate chelator 8 was shown to be more efficient to promote the coupling reactions than our key tetradentate ligand 3. The corresponding N-(1-alkenyl)azoles and alkenyl aryl ethers are obtained in high yields and selectivities under very mild temperature conditions (35-110 degrees C for N-vinylation reactions and 50-80 degrees C for O-vinylation reactions). Moreover, to our knowledge, this method is the first example of a copper-catalyzed vinylation of various azoles. Finally, this protocol, practical on a laboratory scale and easily adaptable to an industrial scale, is very competitive compared to the existing methods that allow the synthesis of such compounds.
报道了一种高效且直接的铜催化方法，该方法可实现用二取代或三取代乙烯基溴对N-或O-亲核试剂进行乙烯基化反应。该方法适用于广泛的底物，因为一唑、二唑和三唑的N-乙烯基化以及酚衍生物的O-乙烯基化反应都可以在催化量的碘化铜和廉价的氮配体3或8存在下进行。对于位阻更大的乙烯基溴，已证明使用原始的双齿螯合剂8比我们的关键四齿配体3更能有效地促进偶联反应。相应的N-(1-烯基)唑和烯基芳基醚在非常温和的温度条件下（N-乙烯基化反应为35-110℃，O-乙烯基化反应为50-80℃）以高收率和选择性得到。此外，据我们所知，该方法是铜催化各种唑进行乙烯基化反应的首例。最后，该方案在实验室规模上切实可行且易于扩大到工业规模，与现有的用于合成此类化合物的方法相比极具竞争力。
