A theoretical view on the thermodynamic cis–trans equilibrium of dihalo ruthenium olefin metathesis (pre-)catalysts

• DOI: 10.1007/s00706-015-1433-8
• Publication Date: 2015-02-23T08:38:49Z
• Authors: Eva Pump; Luigi Cavallo; Christian Slugovc
• Keywords: Olefin metathesis; Density functional theory; Olefin metathesis; Ruthenium; Catalysis; Density functional theory; GAUSSIAN-BASIS SETS; CARBENE COMPLEXES; INDENYLIDENE COMPLEXES; QUINOXALINE COMPLEXES; BENZYLIDENE LIGAND; ATOMS LI; CATALYSTS; GRUBBS; MECHANISM; BEARING; 01 natural sciences; 7. Clean energy; Catalysis; Ruthenium; 0104 chemical sciences

This work was conducted to provide an overview on the position of the thermodynamic cis–trans equilibrium of 85 conventional and X-chelated alkylidene-ruthenium complexes (X=O, S, Se, N, P, Cl, I, Br). The reported energies (ΔE) were obtained through single-point calculations with M06 functional and TZVP basis set from BP86/SVP-optimized cis- and trans-dichloro geometries and using the polarizable continuum model to simulate the influence of the solvent. Dichloromethane and toluene were selected as examples for solvents with high and low dielectric constants. The obtained relative stabilities of the cis- and trans-dihalo derivatives of the respective alkylidene complexes will serve for a better explanation of their catalytic activity as has been disclosed herein with selected examples.