Catalytic hydrogenation of carbonyl and nitro compounds using an [N,O]-chelate half-sandwich ruthenium catalyst
Zi-Jian Yao1, Jing-Wei Zhu2, Nan Lin2
1School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, 201418, China. zjyao@sit.edu.cn and State Key Laboratory of Molecular Engineering and Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Material, Fudan University, Shanghai, 200433, China.
Abstract:
A series of N,O-chelate half-sandwich ruthenium complexes for both carbonyl and nitro compound hydrogenation have been synthesized based on β-ketoamino ligands. All complexes exhibited high activity for the catalytic hydrogenation of a series of ketones and nitroarenes with molecular H2 as the reducing reagent in aqueous medium. Consequently, the catalytic system showed the catalytic TON values of 950 for 1-phenylethanol in acetophenone hydrogenation and 1960 for 1-chloro-4-nitrobenzene in p-chloroaniline hydrogenation. Good catalytic activity was displayed for various kinds of substrates with either electron-donating or electron-withdrawing groups. The neutral ruthenium complexes 1-4 were fully characterized using NMR, IR, and elemental analysis. Molecular structures of complexes 2 and 4 were further confirmed using single-crystal X-ray diffraction analysis.
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