MALDI and ESI-MS have been applied to the characterization of the reaction products between the labile cis-[Pt(DMSO)(2)Cl-2 (1) and trans-[Pt(DMSO)(2)Cl(CH3)] (2) complexes with the simplest poly(amidoamine) ligand (PAMAM, G = 0, 1,2-diaminoethane as core). The comparison of the mass spectra of the starting Go and those of the metallo-dendrimers formed upon mixing of the reagents in an equimolecular ratio, and the analysis of the isotopic distribution in the ESI spectra, have revealed the formation of cationic and neutral mononuclear complexes with PAMAM as ligand, e.g., cis-[Pt(DMSO)(PAMAM)Cl]Cl or trans-(C,N)[Pt(DMSO)(PAMAM)Cl(CH3)], together with various minor components, which have been identified as derivatives from defective structures of PAMAM. The geometry of the main products has been deduced from the values of the protons coupling constants with the isotopically abundant (195)pt. The metal-to-ligand bond is restricted to the peripheral amino groups of PAMAM which shows sufficient flexibility to involve either one or two branches in the coordination bonding. (c) 2004 Elsevier B.V. All rights reserved.
Synthesis and characterization of poly(amidoamine)-platinum(II) complexes. Detailed speciation by matrix-assisted laser desorption ionization mass spectrometry
GAROZZO, DOMENICO;
2005-01-01
Abstract
MALDI and ESI-MS have been applied to the characterization of the reaction products between the labile cis-[Pt(DMSO)(2)Cl-2 (1) and trans-[Pt(DMSO)(2)Cl(CH3)] (2) complexes with the simplest poly(amidoamine) ligand (PAMAM, G = 0, 1,2-diaminoethane as core). The comparison of the mass spectra of the starting Go and those of the metallo-dendrimers formed upon mixing of the reagents in an equimolecular ratio, and the analysis of the isotopic distribution in the ESI spectra, have revealed the formation of cationic and neutral mononuclear complexes with PAMAM as ligand, e.g., cis-[Pt(DMSO)(PAMAM)Cl]Cl or trans-(C,N)[Pt(DMSO)(PAMAM)Cl(CH3)], together with various minor components, which have been identified as derivatives from defective structures of PAMAM. The geometry of the main products has been deduced from the values of the protons coupling constants with the isotopically abundant (195)pt. The metal-to-ligand bond is restricted to the peripheral amino groups of PAMAM which shows sufficient flexibility to involve either one or two branches in the coordination bonding. (c) 2004 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
