Electrochemical and Light-driven CO2 reduction by Amine-Functionalized rhenium Catalysts: A comparison between primary and tertiary amine substitutions
Electrochemical and Light-driven CO2 reduction by Amine-Functionalized rhenium Catalysts: A comparison between primary and tertiary amine substitutions
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DOI：
10.1016/j.poly.2022.115976
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发表时间：
2022-06
期刊：
影响因子：
2.6
通讯作者：
Sayontani Sinha Roy;Kallol Talukdar;Sha Tamanna Sahil;J. W. Jurss
中科院分区：
文献类型：
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作者：
Sayontani Sinha Roy;Kallol Talukdar;Sha Tamanna Sahil;J. W. Jurss
适当定位的第二配位球官能团可以在增强催化活性、改变产物选择性和/或降低所需化学转化的能量成本方面发挥不可或缺的作用。在此背景下，我们研究了fac-Re（bpy）（CO）3Cl（ReBpy）催化剂骨架（bpy为2，2 ′-联吡啶）中第二球叔胺基团的作用。合成并表征了一类在2，2 ′-联吡啶6位上带有N，N-二甲基苯胺（DMA）取代基的Re（bpy）异构体催化剂，其中-NMe 2基团分别位于苯环的邻位、Meta位和对位，以系统地改变胺与金属中心的距离.对位取代的配合物（Re-pNMe 2）在优化的电化学和光化学条件下分别以最高的转换频率（168 s-1）和最高的转换数（80）领先于系列。进行光谱电化学实验，以确定参与这些配合物的催化循环的还原中间体。此外，催化参数进行了比较与类似的和以前报道的一系列的Re催化剂轴承-NH 2功能在第二协调领域。我们的研究结果表明，与苯胺取代的伯胺系统，催化与DMA取代的叔胺配合物主要是由诱导电子效应。
Properly positioned second-coordination sphere functional groups can play an integral role in enhancing catalytic activity, altering product selectivity, and/or reducing the energy cost for desired chemical transformations. In this context, we have investigated the effect of second-sphere tertiary amine groups in thefac-Re(bpy)(CO)3Cl (ReBpy) catalyst scaffold (bpy is 2,2′-bipyridine). A family of isomeric Re(bpy) catalysts bearingN,N-dimethylaniline (DMA) substituents at the 6 position of 2,2′-bipyridine has been synthesized and characterized, where the -NMe2group of each complex is installed at theortho,meta, orparaposition of the pendant phenyl ring to systematically vary the distance between the amine and the rhenium metal center. Thepara-substituted complex (Re-pNMe2) leads the series with the highest turnover frequency (168 s−1) and highest turnover number (80) measured under optimized electrochemical and photochemical conditions, respectively. Spectroelectrochemical experiments were performed to identify reduced intermediates that are involved in the catalytic cycles of these complexes. In addition, the catalytic parameters have been compared with the analogous and previously reported series of Re catalysts bearing –NH2functionality in the second-coordination sphere. Our results demonstrate that, unlike the aniline-substituted primary amine systems, catalysis with the DMA-substituted tertiary amine complexes is predominantly governed by inductive electronic effects.