Ruthenium-Catalyzed Ortho-Selective C–H Alkenylation of Aromatic Compounds with Alkenyl Esters and Ethers
作者:Yohei Ogiwara、Masaru Tamura、Takuya Kochi、Yusuke Matsuura、Naoto Chatani、Fumitoshi Kakiuchi
DOI:10.1021/om401204h
日期:2014.1.13
elimination. Two types of catalytically relevant species were identified, and the reactivities of these species, combined with the results of the kinetic studies, suggest that the rate-limiting step is the exchange of the COD ligand with the alkenyl ester. On the basis of the elucidated mechanism, the first catalytic coupling reaction using aromatic C–H bonds with C–O bonds of ethers was also developed
使用Ru(cod)(cot)作为催化剂,开发了芳基吡啶基和杂芳基吡啶及相关化合物的芳香族C–H键与烯基酯的直接,区域选择性烯基化反应。使带有电子多样性取代基和各种杂环定向基团的芳族化合物与带有带有脂族和芳族取代基的单和二取代烯基的乙酸烯基酯反应,以高收率得到邻烯基化产物。使用不同比例的E和Z进行氘标记实验和竞争反应的结果β-苯乙烯基乙酸酯的异构体表明,C–H烯基化反应是通过钌–烯烃中间体进行的,乙酸烯基酯的C–O键被β-乙酰氧基消除而裂解。确定了两种类型的催化相关物种,这些物种的反应性与动力学研究的结果相结合,表明限速步骤是COD配体与烯基酯的交换。在阐明机理的基础上,还开发了第一个使用芳族C–H键与醚的C–O键的催化偶联反应。