Lewis Acid‐Promoted Heterogeneous Platinum Catalysts for Hydrogenation of Amides to Amines. Issue 4 (6th April 2016)

• Record Type: Journal Article
• Authors: Shimizu , Ken‐ichi; Onodera, Wataru; Touchy, Abeda S.; Siddiki, S. M. A. H.; Toyao , Takashi; Kon, Kenichi
• Is Part Of: ChemistrySelect. Volume 1:Issue 4(2016)
• Page Start: 736
• Page End: 740
• Publication Date: 2016-04-06
• Subjects: amide hydrogenation -- amines -- Lewis acids -- heterogeneous catalysis -- platinum; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201600088
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: For the hydrogenation of a tertiary amide ( N ‐acetylpiperidine), Lewis acidic support materials (Nb2 O5 and MoOx/TiO2 ) increase the catalytic activity of Pt metal nanoparticles by a factor of >100. In situ infrared (IR) study shows that coordination of the C=O group of amide to surface Lewis acid sites weakens the C=O bond, and the activated amide undergoes hydrogen transfer from H species on Pt sites. Among 19 types of heterogeneous catalysts tested, Pt/Nb2 O5 shows the highest catalytic activity. Pt/Nb2 O5 is generally effective for the selective hydrogenation of various tertiary amides and ɛ‐caprolactam to the corresponding amines under additive‐free and solventless conditions and shows an order of higher turnover number (TON) than previously reported catalysts. Pt‐MoOx/TiO2 is the secondary most effective and is reusable 10 times after the reaction. Abstract : This study demonstrates more than 100‐fold activity improvement of Pt catalysts for the hydrogenation of a tertiary amide by Lewis acidic support materials (Nb2 O5 and MoOx/TiO2 ) driven by Lewis acid activation of the C=O bond of amides. The rationally developed heterogeneous catalysts show high performances under additive‐free and solventless conditions.