Theoretical aspects on water soluble [RuClCp(PPh3)2], [RuClCp(PTA)(PPh3)], [RuClCp(PTA)2], [RuClCp(mPTA)(PPh3)]+ and [RuClCp(mPTA)2]2+ (PTA=1,3,5-triaza-7-phosphaadamantane; mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane)

Resulting complexes by substitution of PPh3 in [RuClCp(PPh3)(2)] by water soluble PTA and mPTA ligand has been investigated. Molecular and electronic structures of complexes [RuClCp(PPh3)(2)] (1), [RuClCp(PTA)(PPh3)] (2), [RuClCp(PTA)(2)] (3), [RuClCp(mPTA)(PPh3)](+) (4) and [RuClCp(mPTA)(2)](2+) (5) and the ligands PPh3, PTA and mPTA (PTA = 1,3,5-triaza-7-phosphaadamantane; mPTA = N-methyl-1,3,5-triaza-7-phosphaadamantane) have been investigated using molecular mechanics and density functional theory methods. Natural bond orbital analysis shows that the Ru is linked to the PPh3 and PTA by a 2-center bond with main participation of metal d functions and p functions of the phosphorus atoms. A combined density functional theory/continuum electrostatics approach has been used to estimate the Delta G values of the substitution reactions in gas-phase. The effect on Delta G values of the bulk acetone medium was calculated by inclusion of the polarizable continuum model (PCM). The harmonic vibrational frequencies were calculated by using methods of density functional theory and compared with the experimental values, (C) 2008 Elsevier B.V. All rights reserved.