Cyclometalated Ruthenium Catalyst Enables Ortho-Selective C–H Alkylation with Secondary Alkyl Bromides
作者:Gang-Wei Wang、Matthew Wheatley、Marco Simonetti、Diego M. Cannas、Igor Larrosa
DOI:10.1016/j.chempr.2020.04.006
日期:2020.6
meta-selective sp2 C–H alkylation with secondary alkyl halides is well established, ortho selectivity has never been achieved. We demonstrate that the use of a cyclometalated Ru-complex, RuBnN, as the catalyst results in a complete switch of the inherent meta-selectivity to ortho selectivity in the Ru-catalyzed sp2 C–H alkylation reaction with unactivated secondary alkyl halides. The high catalytic activity
尽管已经很好地确定了Ru催化的具有仲烷基卤化物的间选择性sp 2 C–H烷基化反应,但邻位选择性从未实现。我们证明,使用的环金属钌络合物,RuBnN,如在固有的一个完整的开关催化剂结果元-选择性到邻位选择性Ru-催化SP 2C–H烷基化反应与未活化的仲烷基卤化物。RuBnN的高催化活性允许温和的反应条件,导致宽范围和多功能性的转变。初步的机理研究表明,双环钌化物种是与烷基溴发生氧化加成反应的关键中间体,因此避免了与间位选择性相关的更常见的SET途径。