Modifiable Sulfur Tethers as Directing Groups for Aromatic CH Acetoxylation Reactions
作者:Heinrich Richter、Stephan Beckendorf、Olga García Mancheño
DOI:10.1002/adsc.201000941
日期:2011.2.11
A designed new class of modifiable sulfur tethers for aromatic CH bond functionalizations is presented. As a model, the palladium-catalyzed directed acetoxylation reaction was studied. The more challenging sulfoxide tethers were the most effective in this transformation, showing a broad functionality tolerance, high S oxido-redox stability and no catalyst poisoning. Preliminary mechanistic studies
提出了一种设计用于芳香族CH键官能化的新型可修饰硫系链。作为模型,研究了钯催化的直接乙酰氧基化反应。更具挑战性的亚砜系链在此转化中最有效,表现出宽泛的功能耐受性,高S氧化还原稳定性和无催化剂中毒。初步的机理研究表明,亚砜系链相对于相应的砜显示出更高的反应性和选择性,可以归因于亚砜S原子与催化剂的额外配位。还举例说明了所提出的方法通过随后对S-链的修饰来产生结构上令人感兴趣的芳族衍生物的实用性。