1. Ruthenium‐to‐Platinum Interactions in η 6 ,η 1 NCN‐Pincer Arene Heterobimetallic Complexes: An Experimental and Theoretical Study
- Author
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Bonnet, S., Siegler, M. A., van Lenthe, J.H., Lutz, M., Spek, A.L., van Koten, G., Klein Gebbink, R.J.M., Organic Chemistry and Catalysis, Rontgen participation programme, Theoretical Chemistry, Sub Theoretical Chemistry, Sub Crystal and Structural Chemistry, and Sub Chem Biol & Organic Chem begr 1-6-12
- Subjects
Steric effects ,Chemistry ,chemistry.chemical_element ,Arenes ,Heterometallic complexes ,Electrochemistry ,Photochemistry ,Ruthenium ,Pincer movement ,Inorganic Chemistry ,Metal ,Density functional calculations ,Crystallography ,Covalent bond ,visual_art ,visual_art.visual_art_medium ,Molecule ,Platinum - Abstract
A series of η6,η1-heterobimetallic complexes have been prepared in which a [Ru(η6-arene)(C5R5)]+ fragment (R = H or Me) and an η1-NCN-pincer platinum fragment are combined within the same molecule. In complexes [2]+ and [3]+, the ruthenium and platinum centers are η6 and η1 coordinated, respectively, to the same arene ring, whereas in [4A]+ and [5A]+ they are coordinated to two different arene rings that are linked with a covalent bond ([4A]+) or an ethyl bridge ([5A]+). Upon changing the organic manifold between both metal centers, very strong ([2]+) to very weak ([5A]+) ruthenium- to-platinum interactions are obtained. Experimentally, X-ray crystal structures show an increaing steric hindrance when the Ru–Pt distance diminishes, and electrochemical and 195Pt NMR spectroscopic studies show a decreasing electron density on platinum from [5A]+ to [2]+. Theoretical DFT calculations were undertaken, which show an increasing charge on platinum from [5A]+ to [2]+. Our theoretical analysis shows that the particularly strong ruthenium-to-platinum electronic interactions in [2]+ and [3]+ do not come from binding of ruthenium to platinum, but from the pincer Cipso sharing its electron density between both metal centers, which decreases the σ donation to platinum, and from increased backdonation of the platinum d electrons into the π system of the arene ring.
- Published
- 2010
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