Selective Hydrogenation and Hydrodeoxygenation of Aromatic Ketones to Cyclohexane Derivatives Using a Rh@SILP Catalyst. Issue 29 (27th May 2020)

• Record Type: Journal Article
• Authors: Moos, Gilles; Emondts, Meike; Bordet, Alexis; Leitner, Walter
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 29(2020)
• Page Start: 11977
• Page End: 11983
• Publication Date: 2020-05-27
• Subjects: hydrodeoxygenation -- ionic liquids -- nanoparticles -- rhodium -- supported ionic liquid phases; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201916385
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Rhodium nanoparticles immobilized on an acid‐free triphenylphosphonium‐based supported ionic liquid phase (Rh@SILP(Ph3 ‐P‐NTf2 )) enabled the selective hydrogenation and hydrodeoxygenation of aromatic ketones. The flexible molecular approach used to assemble the individual catalyst components (SiO2, ionic liquid, nanoparticles) led to outstanding catalytic properties. In particular, intimate contact between the nanoparticles and the phosphonium ionic liquid is required for the deoxygenation reactivity. The Rh@SILP(Ph3 ‐P‐NTf2 ) catalyst was active for the hydrodeoxygenation of benzylic ketones under mild conditions, and the product distribution for non‐benzylic ketones was controlled with high selectivity between the hydrogenated (alcohol) and hydrodeoxygenated (alkane) products by adjusting the reaction temperature. The versatile Rh@SILP(Ph3 ‐P‐NTf2 ) catalyst opens the way to the production of a wide range of high‐value cyclohexane derivatives by the hydrogenation and/or hydrodeoxygenation of Friedel–Crafts acylation products and lignin‐derived aromatic ketones. Abstract : Some like it hot : Rhodium nanoparticles immobilized on an acid‐free triphenylphosphonium‐based supported ionic liquid phase (Rh@SILP(Ph3 ‐P‐NTf2 )) enabled ready access to high‐value cyclohexane derivatives from aromatic ketones. The product distribution could be switched with high selectivity between the completely hydrogenated (alcohol) and hydrodeoxygenated (alkane) products by changing the reaction temperature (see scheme).