%0 Journal Article
%A Adams, Richard D.
%A Captain, Burjor
%A Fu, Wei
%A Pellechia, Perry J.
%D 2003
%T Dynamical Intramolecular Metal-to-Metal Ligand Exchange of Phosphine
and Thioether Ligands in Derivatives PtRu5(CO)16(μ6-C)
%U https://acs.figshare.com/articles/journal_contribution/Dynamical_Intramolecular_Metal-to-Metal_Ligand_Exchange_of_Phosphine_and_Thioether_Ligands_in_Derivatives_PtRu_sub_5_sub_CO_sub_16_sub_sub_6_sub_-C_/3606969
%R 10.1021/ic0207000.s002
%2 https://acs.figshare.com/ndownloader/files/5695020
%K PMe 2 Ph ligands
%K phosphine ligand
%K metal atoms
%K compound
%K NMR
%K PMe 2 Ph
%K 2 S ligand
%K complexes PtRu 5
%K Ru atoms
%K PtRu 5
%K kcal
%K Δ G 298
%K CO
%K cal
%K isomer
%K carbido carbon atom
%K Derivatives PtRu 5
%K 2 S ligands
%K isomerization
%X The complexes PtRu5(CO)15(PMe2Ph)(μ6-C) (2), PtRu5(CO)14(PMe2Ph)2(μ6-C) (3), PtRu5(CO)15(PMe3)(μ6-C) (4),
PtRu5(CO)14(PMe3)2(μ6-C) (5), and PtRu5(CO)15(Me2S)(μ6-C) (6) were obtained from the reactions of PtRu5(CO)16(μ6-C) (1) with the appropriate ligand. As determined by NMR spectroscopy, all the new complexes exist in solution
as a mixture of isomers. Compounds 2, 3, and 6 were characterized crystallographically. In all three compounds,
the six metal atoms are arranged in an octahedral geometry, with a carbido carbon atom in the center. The PMe2Ph
and Me2S ligands are coordinated to the Pt atom in 2 and 6, respectively. In 3, the two PMe2Ph ligands are
coordinated to Ru atoms. In solution, all the new compounds undergo dynamical intramolecular isomerization by
shifting the PMe2Ph or Me2S ligand back and forth between the Pt and Ru atoms. For compound 2, ΔH⧧= 15.1(3)
kcal/mol, ΔS⧧ = −7.7(9) cal/(mol·K), and ΔG298 = 17.4(6) kcal/mol for the transformation of the major isomer to
the minor isomer; for compound 4, ΔH⧧ = 14.0(1) kcal/mol, ΔS⧧ = −10.7(4) cal/(mol·K), and ΔG298 = 17.2(2)
kcal/mol for the transformation of the major isomer to the minor isomer; for compound 6, ΔH⧧ = 18(1) kcal/mol,
ΔS⧧ = 21(5) cal/(mol·K) and ΔG298 = 12(2) kcal/mol. The shifts of the Me2S ligand in 6 are significantly more
facile than the shifts for the phosphine ligand in compounds 2−5. This is attributed to a more stable ligand-bridged
intermediate for the isomerizations of 6 than that for compounds 2−5. The intermediate for the isomerization of 6
involves a bridging Me2S ligand that can use two lone pairs of electrons for coordination to the metal atoms,
whereas a tertiary phosphine ligand can use only one lone pair of electrons for bridging coordination.
%I ACS Publications