Phosphato complexes of platinum(II): Phosphorus-31 NMR and kinetics of formation and isomerization studies

Journal Article · Wed Sep 05 04:00:00 EDT 1990 · Inorganic Chemistry; (USA)

DOI:https://doi.org/10.1021/ic00343a036· OSTI ID:6170545

Bose, R N; Goswami, N; Moghaddas, S ^[1]

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1. Kent State Univ., OH (USA)

Ortho-, pyro-, and triphosphate anions form monodentate phosphato complexes with chloro(diethylenetriamine)platinum(II) chloride and various chelates with dichloro(ethylenediamine)platinum(II) in the pH range 2-11. Monodentate complexations largely proceed through the direct reaction with the PtCl(dien){sup +}. Phosphorus-31 NMR spectra reveal coordination chemical shifts of 3-6 ppM for the phosphorus atoms of the bound phosphate groups. Only the monodentate ({gamma}-triphosphato)platinum(II) complex was detected by {sup 31}P NMR spectroscopy, although this ligand is capable of coordinating through the {beta}-phosphate group as well. Phosphorus-phosphorus coupling constants for Pt(dien)(H{sub 2}P{sub 2}O{sub 7}) and Pt(dien)(H{sub 2}P{sub 3}O{sub 10}){sup {minus}} complexes were found to be in the range 19-23 Hz. Chelation to dichloro(ethylenediamine)platinum(II) by pyro- and triphosphate ligands is accomplished primarily through aquations of the platinum substrate. The triphosphate ligand forms both {beta},{gamma}- and {alpha}{gamma}-linkage isomers; the six-membered chelate ring ({beta},{gamma}-complex) formation dominates at lower pH (3-4), whereas the formation of the eight-membered chelate ring is favored in the pH range > 6. Coordinated phosphate groups exhibit 4-12 ppM coordination chemical shifts, and phosphorus-phosphorus coupling constants of 19-22 Hz were observed for the triphosphato chelates. Linkage isomerizations, {beta}{gamma} {yields} {alpha},{gamma} and {alpha},{gamma} {yields} {beta},{gamma}, for triphosphato complexes mainly proceed through an intramolecular mechanism. 36 refs., 4 figs., 6 tabs.

• OSTI ID: 6170545
• Journal Information: Inorganic Chemistry; (USA), Journal Name: Inorganic Chemistry; (USA) Vol. 29:18; ISSN 0020-1669; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400202 -- Isotope Effects
Isotope Exchange
& Isotope Separation
ALKENES
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
CHLORINE COMPOUNDS
COMPLEXES
DATA
ETHYLENE
EXPERIMENTAL DATA
HALOGEN COMPOUNDS
HYDROCARBONS
INFORMATION
ISOTOPES
KINETICS
LIGHT NUCLEI
NMR SPECTRA
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PH VALUE
PHOSPHORUS 31
PHOSPHORUS COMPOUNDS
PHOSPHORUS ISOTOPES
PLATINUM COMPLEXES
REACTION KINETICS
SPECTRA
STABLE ISOTOPES
SYNTHESIS
TRANSITION ELEMENT COMPLEXES