Solution and solid-state spectroscopic characterization of chloro dimethylsulfoxide polythioether ruthenium(II) complexes, complemented with DFT calculations in the gas phase

Abstract

Several ruthenium(II)-chloro-dimethylsulfoxide complexes with formulae [RuCl₂(DMSO)(k ³-L₁)] or [RuCl(DMSO)(k ⁴-L₂)]⁺, where L₁ = [9]aneS₃ (2) or ttbt (5) and L₂ = [12]aneS₄ (3), [14]aneS₄ (4) or [14]aneN₄ (6), have been synthesized from cis,fac-[RuCl₂(S-DMSO)₃(O-DMSO)] (1) and the respective macrocycle. They were spectroscopically characterized by FT-IR, FT-Raman, NMR, and UV/Vis. Particular attention was given to fac-[RuCl₂(DMSO)(k ³-ttbt)] (5), the first octahedral complex of ttbt, which was also studied by DFT calculations. The behavior of the complexes in coordinating solvents water, acetonitrile, and dimethylsulfoxide was studied to understand their reactivity and predict the resulting ions formed in solution. The role of the counter ion (Cl⁻ vs. ) was also evaluated. The results indicate that the chosen macrocycle, the counter-ion, and the solvent have a direct impact on the chemical species formed in solution.

keywords:

• Ruthenium
• Crown thioethers
• Counter-ion
• Solvolysis
• Molecular modeling

Acknowledgements

Dr Paula Ferreira and Prof. Graça Santana-Marques (University of Aveiro) are thanked for running solid-state ¹³C NMR and ESI-MS analysis, respectively. J.M. thanks FCT (Portugal) for a post-doc grant (SFRH/BPD/41138/2007) and the Center for High Performance Computing (VCU) for access to bach.vcu.edu cluster.