Investigating Oxidative Addition Mechanisms of Allylic Electrophiles with Low-Valent Ni/Co Catalysts Using Electroanalytical and Data Science Techniques
作者:Tianhua Tang、Eli Jones、Thérèse Wild、Avijit Hazra、Shelley D. Minteer、Matthew S. Sigman
DOI:10.1021/jacs.2c09120
日期:2022.11.2
the critical oxidative addition mechanism to form the π-allyl-Co/Ni complex remains unclear. Herein, we present a study to investigate this process with four catalysis-relevant complexes: Co(MeBPy)Br2, Co(MePhen)Br2, Ni(MeBPy)Br2, and Ni(MePhen)Br2. Enabled by an electroanalytical platform, Co(I)/Ni(I) species were found responsible for the oxidative addition of allyl acetate. Kinetic features of different
由于在还原性 Co/Ni 催化的烯丙基化反应中具有独特的反应性,π-烯丙基-Co/Ni 络合物的催化作用最近引起了广泛关注。尽管在反应开发方面取得了重大成功,但形成 π-烯丙基-Co/Ni 络合物的关键氧化加成机制仍不清楚。在此,我们提出了一项研究,用四种与催化相关的配合物研究该过程:Co( Me BPy)Br 2、Co( Me Phen)Br 2、Ni( Me BPy)Br 2和 Ni( Me Phen)Br 2. 通过电分析平台,发现 Co(I)/Ni(I) 物种负责乙酸烯丙酯的氧化加成。通过线性自由能关系(Hammett 型)研究、统计建模和 DFT 计算研究来表征不同底物的动力学特征。在此过程中,提出了配位电离型过渡态,与 Tsuji-Trost 反应中 Pd(0) 介导的氧化加成具有相似的特征。计算和配体结构分析研究支持这一机制,这将为下一代催化剂的开发提供关键信息。