Synthesis of a CCC‐NHC pincer Re complex: An air stable catalyst for coupling ketones with primary alcohols via borrowing hydrogen
Synthesis of a CCC‐NHC pincer Re complex: An air stable catalyst for coupling ketones with primary alcohols via borrowing hydrogen
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CCC-NHC 钳铼络合物的合成：一种通过借氢将酮与伯醇偶联的空气稳定催化剂
DOI：
10.1002/aoc.6789
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发表时间：
2022
影响因子：
3.9
通讯作者：
Hollis, T. Keith
中科院分区：
文献类型：
--
作者：
Pham, Hoang H.;Donnadieu, Bruno;Hollis, T. Keith
迄今为止，文献中尚未报道Re的CCC-NHC钳形复合物。报道了Re的第一个CCC-NHC钳形络合物。通过1H和13 C核磁共振（NMR）光谱、质谱、元素分析和X射线晶体学方法对其进行了充分表征，以确定分子结构。它是由分离的Zr前体通过transmethalide合成的，并且被发现是空气稳定的。CCC-NHC Re（I）钳形配合物的催化活性被证明用于苄型酮和伯醇之间的借氢偶联反应，以在环境友好的催化中产生新的C-C键，不需要醇官能团的活化基团。这种借氢偶联反应产生化学计量量的水作为唯一的副产物，并且不需要将伯醇转化为离去基团。广泛的基板进行了检查，并获得从53%至92%的分离产率。提出了一种CCC-NHC Re（I）钳形配合物催化的借氢偶联反应的催化循环。
To date, no CCC‐NHC pincer complexes of Re have been reported in the literature. The first CCC‐NHC pincer complex of Re is reported. It was fully characterized by1H and13C nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy, elemental analysis, and X‐ray crystallographic methods to determine the molecular structure. It was synthesized via transmetallation from an isolated Zr precursor and was found to be air stable. The catalytic activity of the CCC‐NHC Re(I) pincer complex was demonstrated for the borrowing hydrogen coupling reaction between benzylic ketones and primary alcohols to generate a new C–C bond in an environmentally friendly catalysis requiring no activating groups for the alcohol functionality. This borrowing hydrogen coupling reaction produced a stoichiometric amount of water as the only by‐product and did not require the conversion of the primary alcohol to a leaving group. A broad range of substrates was examined, and isolated yields from 53% to 92% were obtained. A catalytic cycle for the CCC‐NHC Re(I) pincer complex catalyzed borrowing hydrogen coupling reaction is proposed.