Bifunctional N-heterocyclic carbene ligands for Cu-catalyzed direct C–H carboxylation with CO<sub>2</sub>
作者:Da-Ae Park、Ji Yeon Ryu、Junseong Lee、Sukwon Hong
DOI:10.1039/c7ra11414a
日期:——
Diethylene glycol-functionalized imidazo[1,5-a]pyridin-3-ylidenes (DEG-ImPy) have been developed as bifunctional N-heterocyclic carbene ligands. The DEG-ImPy Cu(I) complexes efficiently catalyzed the direct C–H carboxylation of benzoxazole with CO2, showing higher isolated yields than those with the N,N′-(2,6-diisopropylphenyl)imidazolylidene Cu catalyst.
二甘醇官能化的咪唑并[1,5 - a ]吡啶-3-吡咯(DEG-ImPy)已开发为双官能N杂环卡宾配体。DEG-ImPy Cu(I)配合物有效地催化了CO 2对苯并恶唑的直接C–H羧化反应,显示出比N,N '-(2,6-二异丙基苯基)咪唑基亚苄基Cu催化剂更高的分离产率。
Copper-Catalyzed Direct Carboxylation of CH Bonds with Carbon Dioxide
Cooking with gas: Copper complexes serve as excellent catalysts for the directcarboxylation of aromatic heterocyclic CHbonds with CO2, thereby offering an economical and environmentally benign process for the synthesis of heterocyclic carboxylic esters (see scheme; IPr=1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene). Some active intermediates of this reaction have been isolated and structurally