钌催化剂使具有挑战性的仲烷基卤化物的芳烃上的 CH 键官能化成为可能。特别是,钌 (II) 双羧酸配合物被证明是直接烷基化成功的关键,具有出色的不寻常的间位选择性。直接烷基化发生在温和的反应条件下,具有足够的范围和可耐受的有价值的官能团。进行了详细的机理研究,包括各种竞争实验以及与同位素标记底物的反应。这些研究为最初的可逆环金属化提供了强有力的支持。环钌化从而活化芳烃,用于随后用仲烷基卤化物进行远程亲电型取代。
Cobalt-Catalyzed CH Bond Functionalizations with Aryl and Alkyl Chlorides
作者:Benudhar Punji、Weifeng Song、Grigory A. Shevchenko、Lutz Ackermann
DOI:10.1002/chem.201301409
日期:2013.8.5
catalytic CH bond arylations on heteroaryl‐substituted arenes with widely available aryl chlorides, which set the stage for the preparation of sterically hindered tri‐ortho‐substituted biaryls. Likewise, challenging direct alkylations with β‐hydrogen‐containing primary and even secondary alkyl chlorides proceeded on pyridyl‐ and pyrimidyl‐substituted arenes and heteroarenes. The cobalt‐catalyzed CH bond