New Ru(II) Complexes with Anionic and Neutral N-Donor Ligands as Epoxidation Catalysts: An Evaluation of Geometrical and Electronic Effects
作者:Mohamed Dakkach、M. Isabel López、Isabel Romero、Montserrat Rodríguez、Ahmed Atlamsani、Teodor Parella、Xavier Fontrodona、Antoni Llobet
DOI:10.1021/ic100862y
日期:2010.8.2
spectroscopically characterized in solution through 1H NMR and UV−vis techniques, and the chloro complexes have also been characterized in the solid state through monocrystal X-ray diffraction analysis. The pyrpy ligand undergoes an oxidation at the 3-position of the pyrrolate ring during the formation of the corresponding aqua complex thus generating the analogous compound containing the oxidized ligand pyrpy-O
合成含有通式[Ru II(T)(D)(X)] n +(T = 2,2':6',2''-叔吡啶(trpy ); D = 3,5-二甲基-2-(2-吡啶基)吡咯酸酯(pyrpy)和2-(1-甲基-3-吡唑基)吡啶(pypz-Me); X = Cl,H 2 O)具有被描述。所有配合物均已在溶液中通过1进行了光谱表征还通过单晶X射线衍射分析对H NMR和UV-vis技术以及氯配合物进行了固态表征。相应的水配合物形成过程中,该吡啶基配体在吡咯酸盐环的3位上进行氧化,从而产生含有氧化的配体pyrpy-O的类似化合物。还通过CV和DPV技术研究了所有配合物的氧化还原特性,可以揭示和合理化几何(反式与顺式)和电子(中性与阴离子)效应。最后,就不同烯烃与PhI(OAc)2的环氧化作用,测试了整套Ru-OH 2配合物的反应性。在所有情况下,均获得了良好的选择性和转化率。此外,当使用这些催化剂环氧化顺-β-甲基苯乙烯时,可以完全保留初始的顺式构型。