| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 64588 | Journal of Molecular Catalysis A: Chemical | 2016 | 10 Pages |
•Stable, chirally modified Rh(0) nanoparticles are formed in situ.•These nanoparticles are catalysts for transfer hydrogenation reactions.•Yield and enantioselectivity depend on the chiral modifier and reaction conditions.•Enantiomeric excesses (ee) for products up to 58% ee.•The size of the nanoparticles influences their catalytic activity.
Transfer hydrogenation of acetophenone and methyl benzoylformate with 2-propanol has been studied on rhodium nanoparticles obtained by the reduction of rhodium(I) complexes in the presence of optically active compounds, including chiral diamine S,S-DIODMA, (4S,5S)-N4,N4,N5,N5,2,2-hexamethyl-4,5-bis-(aminomethylene)-1,3-dioxolane, quaternary diammonium salt (4S,5S)-(-)-N1,N4-dibenzyl-2,3-dihydroxy-N1,N1,N4,N4-tetramethylbutane-1,4-diammonium dichloride, and (8S,9R)-(-)-cinchonidine. Increasing the modifier to Rh ratio leads to an increase in the enantiomeric excess (ee) of the reaction products. The greatest ee values (43.8% for (R)-1-phenylethanol and 58.2% for the methyl ester of (R)-mandelic acid) were achieved at (8S,9R)-(-)-cinchonidine/Rh ratios of 9:1 and 3:1, respectively.
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