Experimental and computational investigation on the formation pathway of [RuCl₂(CO)₂(ERR′)₂] (E = S, Se, Te; R, R′ = Me, Ph) from [RuCl₂(CO)₃]₂ and ERR′
|Author:||Taimisto, Marjaana1; Bajorek, Tom1; Rautiainen, J. Mikko2;|
1Laboratory of Inorganic Chemistry, Environmental and Chemical Engineering, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
2Department of Chemistry and Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland
|Online Access:||PDF Full Text (PDF, 1.7 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2022082656380
Royal Society of Chemistry,
|Publish Date:|| 2022-08-26
The pathways to the formation of the series of [RuCl₂(CO)₂(ERR′)₂] (E = S, Se, Te; R, R′ = Me, Ph) complexes from [RuCl₂(CO)₃]₂ and ERR′ have been explored experimentally in THF and CH2Cl2, and computationally by PBE0-D3/def2-TZVP calculations. The end-products and some reaction intermediates have been isolated and identified by NMR spectroscopy, and their crystal structures have been determined by X-ray diffraction. The relative stabilities of the [RuCl₂(CO)₂(ERR′)₂] isomers follow the order cct > ccc > tcc > ttt ≈ ctc (the terms c/t refer to cis/trans arrangement of the ligands in the order of Cl, CO, and ERR′). The yields were rather similar in both solvents, but the reactions were significantly faster in THF than in CH₂Cl₂. The highest yields were observed for the telluroether complexes, and the yields decreased with lighter chalcogenoethers. PBE0-D3/def2-TZVP calculations indicated that the reaction path is independent of the nature of the solvent. The substitution of one CO ligand of the intermediate [RuCl₂(CO)₃(ERR′)] by the second ERR′ shows the highest activation barrier and is the rate-determining step in all reactions. The observed faster reaction rate in THF than in CH₂Cl₂ upon reflux can therefore be explained by the higher boiling point of THF. At room temperature the reactions in both solvents proceed equally slowly. When the reaction is carried out in THF, the formation of [RuCl₂(CO)₂(THF)] is also observed, and the reaction may proceed with the substitution of THF by ERR′. The formation of the THF complex, however, is not necessary for the dissociation of the [RuCl₂(CO)₂]₂. Thermal energy at room temperature is sufficient to cleave one of the bridging Ru–Cl bonds. The intermediate thus formed undergoes a facile reaction with ERR′. This mechanism is viable also in non-coordinating CH₂Cl₂.
|Pages:||11747 - 11757|
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
116 Chemical sciences
Financial support from Finnish Cultural Foundation Lapland Regional Fund, The Finnish Concordia Fund, and Emil Aaltonen Foundation (M. T.), as well as the generous provision of computational resources by Prof. Heikki Tuononen (University of Jyväskylä) (J. M. R.) are also gratefully acknowledged.
© The Royal Society of Chemistry 2022. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.