Surface‐Driven Keto–Enol Tautomerization: Atomistic Insights into Enol Formation and Stabilization Mechanisms. Issue 51 (25th November 2018)

• Record Type: Journal Article
• Authors: Attia, Smadar; Schmidt, Marvin‐Christopher; Schröder, Carsten; Pessier, Pascal; Schauermann, Swetlana
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 51(2018)
• Page Start: 16659
• Page End: 16664
• Publication Date: 2018-11-25
• Subjects: carbonyl compounds -- keto–enol tautomerization on metals -- model heterogeneous catalysis -- scanning tunneling microscopy -- vibrational spectroscopy on surfaces; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201808453
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Tautomerisation of simple carbonyl compounds to their enol counterparts on metal surfaces is envisaged to enable an easier route for hydrogenation of the C=O bond in heterogeneously catalyzed reactions. To understand the mechanisms of enol formation and stabilization over catalytically active metal surfaces, we performed a mechanistic study on keto–enol tautomerization of a monocarbonyl compound acetophenon over Pt(111) surface. By employing infrared reflection adsorption spectroscopy in combination with scanning tunneling microscopy, we found that enol can be formed by building a ketone–enol dimer, in which one molecule in the enol form is stabilized through hydrogen bonding to the carbonyl group of the second ketone molecule. Based on the investigations of the co‐adsorption behavior of acetophenone and hydrogen, we conclude that keto–enol tautomerization occurs in the intramolecular process and does not involve hydrogen transfer through the surface hypothesized previously. Abstract : To understand the mechanisms of enol formation and stabilization over catalytically active metal surfaces, a mechanistic study was performed on keto–enol tautomerization of a monocarbonyl compound, acetophenone, over Pt(111) surface.