TY - JOUR
T1 - 1H and 31P NMR and EPR of Pentaammineruthenium(III)Complexes of Endocyclically Coordinated Nucleotides, Nucleosides, and Related Heterocyclic Bases. Autoxidation of [(GuoκN7)(NH3)5RuIII] (Guo = Guanosine). Crystal Structure of [7MeGuaκN9 (NH3)5Ru]Cl3·3H2O
AU - Rodriguez-Bailey, V. M.
AU - LaChance-Galang, K. J.
AU - Doan, P. E.
AU - Clarke, M. J.
PY - 1997/4/23
Y1 - 1997/4/23
N2 - The 1H-NMR spectra of complexes involving the paramagnetic metal center [(NH3)5RuIII] coordinated at ring nitrogens have been examined with pyridine, purine, nucleoside, and nucleotide ligands along with 31P-NMR of the nucleotide complexes and EPR of representative complexes. Variations in the spectra have been investigated as a function of the coordination site and pH. Pseudocontact and contact shifts have been calculated for various protons, and an attempt has been made to correlate sugar conformations in coordinated 5′GMP, 5′IMP, Guo, and Ino with paramagnetically induced shifts. The compound [(7MeGUaκN9)(NH3)5Ru]Cl 3·3H2O crystallizes in the orthorhombic space group Pna21 with cell parameters a = 25.375(4) Å, b = 11.803(4) Å, c = 6.958(2) Å, Z = 4, and R = 0.042. The autoxidation of [L(NH3)5RuIII], where L = Guo, dGuo, and 1MeGuo, to the corresponding 8-oxo complexes under atmospheric oxygen is first order in the complex and [OH-]. For L = Guo, k = 6.6 × 10-5 M-1 s-1, ΔH* = 58 kJ/mol, and ΔS* = -124 J/(mol K).
AB - The 1H-NMR spectra of complexes involving the paramagnetic metal center [(NH3)5RuIII] coordinated at ring nitrogens have been examined with pyridine, purine, nucleoside, and nucleotide ligands along with 31P-NMR of the nucleotide complexes and EPR of representative complexes. Variations in the spectra have been investigated as a function of the coordination site and pH. Pseudocontact and contact shifts have been calculated for various protons, and an attempt has been made to correlate sugar conformations in coordinated 5′GMP, 5′IMP, Guo, and Ino with paramagnetically induced shifts. The compound [(7MeGUaκN9)(NH3)5Ru]Cl 3·3H2O crystallizes in the orthorhombic space group Pna21 with cell parameters a = 25.375(4) Å, b = 11.803(4) Å, c = 6.958(2) Å, Z = 4, and R = 0.042. The autoxidation of [L(NH3)5RuIII], where L = Guo, dGuo, and 1MeGuo, to the corresponding 8-oxo complexes under atmospheric oxygen is first order in the complex and [OH-]. For L = Guo, k = 6.6 × 10-5 M-1 s-1, ΔH* = 58 kJ/mol, and ΔS* = -124 J/(mol K).
UR - http://www.scopus.com/inward/record.url?scp=0001445309&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0001445309&partnerID=8YFLogxK
U2 - 10.1021/ic9609416
DO - 10.1021/ic9609416
M3 - Article
C2 - 11669793
AN - SCOPUS:0001445309
SN - 0020-1669
VL - 36
SP - 1873
EP - 1883
JO - Inorganic chemistry
JF - Inorganic chemistry
IS - 9
ER -