Influence of a Metal Substrate on Small‐Molecule Activation Mediated by a Surface‐Adsorbed Complex. Issue 42 (27th June 2018)

• Record Type: Journal Article
• Authors: Schlimm, Alexander; Stucke, Nadja; Flöser, Benedikt M.; Rusch, Talina; Krahmer, Jan; Näther, Christian; Strunskus, Thomas; Magnussen, Olaf M.; Tuczek, Felix
• Is Part Of: Chemistry. Volume 24:Issue 42(2018)
• Page Start: 10732
• Page End: 10744
• Publication Date: 2018-06-27
• Subjects: carbonyl ligands -- molybdenum -- monolayers -- surface chemistry -- vibrational spectroscopy; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201800911
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Activating small molecules with transition metal complexes adsorbed on metal surfaces is a novel approach combining aspects of homogeneous and heterogeneous catalysis. In order to study the influence of an Au(111) substrate on the activation of the small‐molecule ligand carbon monoxide, a molybdenum tricarbonyl complex containing a PN 3 P pincer ligand was synthesized and investigated in the bulk, in solution, and adsorbed on an Au(111) surface. By means of a platform approach, a perpendicular orientation of the molybdenum complex was achieved and confirmed by IRRAS and NEXAFS. By using vibrational spectroscopy (IR, Raman, IRRAS) coupled to DFT calculations, the influence of the metal substrate on the activation of the CO ligands bound to the molybdenum complex was determined. The electron‐withdrawing behavior of gold causes an overall shift of the CO stretching vibrations to higher frequencies, which is partly compensated by dynamic charge transfer from the substrate to the molybdenum center, which increases its (dynamic) polarizability. Abstract : A new platform for small‐molecule activation was developed by synthesizing a Mo(CO)3 complex supported by a pincer ligand and connected to a TATA moiety, which was characterized in solution, in the bulk, and adsorbed on Au(111), as shown in the figure. Various surface‐spectroscopic methods revealed a zero‐valent Mo center and a perpendicular orientation of the complex with respect to the surface, and IRRAS measurements revealed a distinct influence of the gold substrate on the activation of the carbonyl ligands.