4.7 Article

On Homogeneous Gold/Palladium Catalytic Systems

期刊

ADVANCED SYNTHESIS & CATALYSIS
卷 354, 期 1, 页码 133-147

出版社

WILEY-V C H VERLAG GMBH
DOI: 10.1002/adsc.201000044

关键词

allenes; allylic esters; aryl halides; gold; heterocycles; palladium

资金

  1. Chinesisch-Deutsches Zentrum [GZ 419 (362/3)]
  2. Deutsche Forschungsgemeinschaft [HA 1932/11-1]
  3. Studienstiftung des dt. Volkes e.V.

向作者/读者索取更多资源

Two substrates containing an aryl iodide and an allenoate ester were prepared and the gold-induced cycloisomerisation to vinylgold(I) species and their proto-deauration as well as the intramolecular palladium-catalysed cross-coupling reactions were investigated. Switching to catalytic amounts of gold and palladium and stoichiometric amounts of silver did indeed furnish the product of a cycloisomerisation/intramolecular cross-coupling. Control experiments revealed that silver cannot substitute for gold or palladium in these reactions, but a different palladium catalyst in a different oxidation state also afforded the cycloisomerisation/intramolecular cross-coupling products in only slightly reduced yields. By ICP analysis the palladium was shown to contain gold only at the sub-ppm level. This shows how carefully results obtained with such systems have to be interpreted. Then a series of allylic and benzylic o-alkynylbenzoates were investigated in gold- and palladium-catalysed reactions. For esters of benzyl alcohol and cinnamyl alcohol no palladium co-catalyst was needed for the conversion. All reagents were thoroughly checked for palladium traces by ICP analysis in order to thoroughly exclude a gold/palladium co-catalysis. Optimisation of the gold complex, counter ion and solvent showed that gold(I) isonitrile pre-catalysts and silver triflate as activator in dioxane are suitable to convert a number of substrates with aryl, alkyl and even cyclopropyl substituents. Crossover experiments proved an intermolecular allyl transfer.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据