Abstract
Three half-sandwich Ru(II) complexes with the general formulae of [Ru(\(\eta\) 6-p-cymene)(L)Cl2] (where L: 2a (diethyl-4-aminobenzylphosphonate), 2b (4-aminoethylbenzoate) and 2c (4-methoxybenzylamine) containing an aniline ligands were synthesized and their structures were characterized. The Crystal structure of complex [Ru(\(\eta\) 6-p-cymene)(2c)Cl2] was investigated by single crystal X-ray diffraction studies. Each Ru(II) ion in both complexes is coordinated with a 6-p-cymene nitrogen atom, two chloride and aniline derivatives. This results in a distorted piano-stool geometry. The catalytic performances of the complexes were investigated in transfer hydrogenation reactions. The complexes catalyze the transfer hydrogenation of cyclohexanone and 2-hexanone in the presence of a base. For 2-hexanone to 2-hexanol reduction, complex [Ru(\(\eta\) 6-p-cymene)(2a)Cl2] showed the highest conversion rate (at the end of 6 h) with 97% conversion. The complexes were found to be more active catalysts in the transfer hydrogenation of cyclohexanone than that of 2-hexanone.
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The author thanks to Research Coordination Unit of Kahramanmaras Sutcu Imam University for financial support (project number: 2018/2-9 YLS) and postdoc (DOSAP) Scholarship (İrfan Şahin).
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Şahin, İ., Sevim, S. & Köse, M. Synthesis, characterization and catalytic transfer hydrogenation properties of Ru(II) complexes. Transit Met Chem 47, 77–84 (2022). https://doi.org/10.1007/s11243-021-00488-y
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DOI: https://doi.org/10.1007/s11243-021-00488-y