Yoshikai Naohiko, Matsuda Hirokazu, Nakamura Eiichi
Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
J Am Chem Soc. 2008 Nov 19;130(46):15258-9. doi: 10.1021/ja807000a. Epub 2008 Oct 25.
Mechanistic studies of the Ni-catalyzed cross-coupling reaction of Grignard reagents through analysis of kinetic isotope effects and theoretical calculations indicated that the product-to-substrate ligand exchange process is the first irreversible step and affects the turnover efficiency and selectivity of the reaction. On the other hand, the oxidative addition step is the first irreversible step in Pd catalysis. This finding has useful implications for the development of efficient Ni catalysis and also illustrates the importance of the catalyst turnover step that has so far received less attention than subsequent catalytic steps.
通过动力学同位素效应分析和理论计算对镍催化格氏试剂交叉偶联反应进行的机理研究表明，产物与底物的配体交换过程是首个不可逆步骤，并影响反应的周转效率和选择性。另一方面，氧化加成步骤是钯催化中的首个不可逆步骤。这一发现对高效镍催化的发展具有有益启示，也说明了催化剂周转步骤的重要性，该步骤迄今受到的关注少于后续催化步骤。
