Weigand Klaus, Pelka Sylvie
Novartis Research Institute, Brunner Strasse 59, A-1235 Vienna, Austria.
Org Lett. 2002 Dec 26;4(26):4689-92. doi: 10.1021/ol027119s.
[reaction: see text] The first examples of the Pd(0)-catalyzed amination of aryl halides using Rink-resins as nitrogen source are described. Pd(2)dba(3)/BINAP/NaO-t-Bu was found to be the most efficient catalyst/base system, while a solvent mixture of dioxane and tert-butyl alcohol was shown to enhance the selectivity toward the desired monoarylation. Moderate to good yields and excellent purities of the amination products were found with electron-poor aryl halides, while electon-rich aryl halides failed to react under these conditions.
[反应:见正文] 描述了使用Rink树脂作为氮源,钯(0)催化芳基卤化物胺化反应的首例实例。发现Pd₂(dba)₃/BINAP/叔丁醇钠是最有效的催化剂/碱体系,而二氧六环和叔丁醇的混合溶剂可提高对所需单芳基化反应的选择性。贫电子芳基卤化物的胺化产物收率中等至良好,纯度优异,而富电子芳基卤化物在这些条件下不发生反应。