(R,R)-DPEN-modified Ru/γ-Al2O3—An efficient heterogeneous catalyst for enantioselective hydrogenation of acetophenone
| Autor: | Chunyu Xi, Hongjun Wang, Jianmin Hao, Fengyu Zhao, Shuxia Cai, Xiangchun Meng, Haiyang Cheng |
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| Rok vydání: | 2007 |
| Předmět: |
chemistry.chemical_classification
Ketone Process Chemistry and Technology Asymmetric hydrogenation Enantioselective synthesis Heterogeneous catalysis Medicinal chemistry Catalysis chemistry.chemical_compound chemistry Organic chemistry Physical and Theoretical Chemistry Enantiomeric excess Phosphine Acetophenone |
| Zdroj: | Journal of Molecular Catalysis A: Chemical. 278:6-11 |
| ISSN: | 1381-1169 |
| DOI: | 10.1016/j.molcata.2007.08.015 |
| Popis: | An efficient enantioselective catalyst of 5 wt.% Ru/γ-Al2O3 modified with R,R-1,2-diphenylethylene-diamine ((R,R)-DPEN) for the hydrogenation of a non-activated aromatic ketone of acetophenone has been investigated, a relatively high enantiomeric excess (ee) of 60.5% was obtained at both the conversion and selectivity larger than 99%, it was about three times higher than the ee values reported up to now for acetophenone hydrogenation with the supported transition metal catalysts modified by chiral reagents. The influences of some reaction parameters such as phosphine ligand, substrate/catalyst/modifier molar ratios, base, solvent, pressure and reaction temperature have been discussed. The chiral modifier of (R,R)-DPEN was very important in controlling the enantioselectivity through adsorption competing with other substrates on the surface of active metal species. The phosphine ligand and base were also important and indispensable in the present reaction. |
| Databáze: | OpenAIRE |
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