Although Ru-catalyzed 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 of RuBnN allows mild reaction conditions that result in a transformation of broad scope and versatility. Preliminary mechanistic studies suggest that a bis-cycloruthenated species is the key intermediate undergoing oxidative addition with the alkyl bromides, thus avoiding the more common SET pathway associated with meta-selectivity.

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。