Direct Identification of Acetaldehyde Formation and Characterization of the Active Site in the [VPO4].+/C2H4 Couple by Gas‐Phase Vibrational Spectroscopy. (8th November 2019)

• Record Type: Journal Article
• Authors: Li, Ya‐Ke; Debnath, Sreekanta; Schlangen, Maria; Schöllkopf, Wieland; Asmis, Knut R.; Schwarz, Helmut
• Is Part Of: Angewandte Chemie. Volume 131:Number 52(2019)
• Page Start: 19044
• Page End: 19048
• Publication Date: 2019-11-08
• Subjects: Aktives Zentrum -- Heteronukleare Oxidcluster -- IR-Photodissoziationsspektroskopie -- Kryogene Ionenfalle -- Olefin-Oxidation; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201911040
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: The gas‐phase reaction of the heteronuclear oxide cluster [VPO4 ] .+ with C2 H4 is studied under multiple collision conditions at 150 K using cryogenic ion‐trap vibrational spectroscopy combined with electronic structure calculations. The exclusive formation of acetaldehyde is directly identified spectroscopically and discussed in the context of the underlying reaction mechanism. In line with computational predictions it is the terminal P=O and not the V=O unit that provides the oxygen atom in the barrier‐free thermal C2 H4 →CH3 CHO conversion. Interestingly, in the course of the reaction, the emerging CH3 CHO product undergoes a rather complex intramolecular migration, coordinating eventually to the vanadium center prior to its liberation. Moreover, the spectroscopic structural characterization of neutral C2 H4 O deserves special mentioning as in most, if not all, ion/molecule reactions, the neutral product is usually only indirectly identified. Abstract : Die Gasphasenreaktion des heteronuklearen Oxidclusters [VPO4 ] .+ mit C2 H4 wurde durch Infrarot‐Photodissoziationsspektroskopie untersucht. Hierbei wurde die Bildung von Acetaldehyd beobachtet und die terminale P=O‐Einheit als aktives Zentrum von [VPO4 ] .+ für den Sauerstoffatomtransfer auf Ethylen identifiziert, was in Einklang mit theoretischen Voraussagen ist.