Complex formation between palladium(II) and amino acids, peptides and related ligands

Two new hexadentate N2O4 donor Schiff bases, H4L1 and H4L2, were synthesized by condensation of 4,6-diacetylresorcinol with glycine and alanine, respectively. The structures of the ligands were elucidated by elemental analyses, IR, 1H NMR, electronic, and mass spectra. Reactions of the Schiff bases with copper(II), nickel(II), and iron(III) nitrates in 1 : 2 molar ratio gave binuclear metal complexes and, in the presence of 8-hydroxyquinoline (8-HQ) or 1,10-phenanthroline (Phen) as secondary ligands (L′), mixed-ligand complexes in two molar ratios 1 : 2 : 2 and 1 : 2 : 1 (L1/L2 : M : L′). The complexes were characterized by elemental and thermal analyses, IR, electronic, mass, and ESR spectral studies, as well as conductivity and magnetic susceptibility measurements. The spectroscopic data reveal that the Schiff-base ligands were dibasic or tetrabasic hexadentate ligands. The coordination sites with the metal ions are two azomethine nitrogens, two oxygens of phenolic groups, and two oxygens of carboxylic ...

Synthesis, spectral studies, and antimicrobial activity of binary and ternary Cu(II), Ni(II), and Fe(III) complexes of new hexadentate Schiff bases derived from 4,6-diacetylresorcinol and amino acids

Within the framework of our research activities related to the partitioning of spent nuclear-fuel solutions, the direct selective extraction of trivalent actinides from a simulated PUREX raffinate was studied using a mixture of CyMe4BTBP and TODGA (1-cycle SANEX). The solvent showed a high selectivity for trivalent actinides with a high lanthanide separation factor. However, the coextraction of some fission product elements (Cu, Ni, Zr, Mo, Pd, Ag, and Cd) from a simulated PUREX raffinate was observed, with distribution ratios up to 30 (Cu). The extraction of Zr and Mo could be suppressed using oxalic acid but the use of the well-known Pd complexant N-(2-Hydroxyethyl)-ethylendiamin-N,N′,N′-triacetic acid (HEDTA) was unsuccessful. During screening experiments with different amino acids and derivatives, the sulfur-bearing amino acid L-Cysteine showed good complexation of Pd and prevented its extraction into the organic phase without influencing the extraction of the trivalent actinides Am (III) and...

Direct Selective Extraction of Actinides (III) from PUREX Raffinate using a Mixture of CyMe4BTBP and TODGA as 1-cycle SANEX Solvent

Publisher Summary This chapter discusses the perchlorate ion complexes. Coordination of perchlorate to transition and nontransition metal ions has been well established, though in most of the cases the metal-perchlorate bond is rather weak and has been termed as “semicoordination”. The highly symmetrical perchlorate ion is a hard base and falls into the category of relatively nonpolarizable and noncoordinating anions such as BF 4 ˉ and PF 6 ˉ. Its ability to coordinate strongly to soft metal ions is therefore limited. When coordination does occur, the perchlorate group may be linked to a metal ion in a monodentate and/or bidentate manner through oxygen atoms; the latter linkage can be either chelating. X-ray crystal structure analysis has unequivocally established coordination of perchlorate in a number of perchlorate complexes.

Perchlorate Ion Complexes

M.R. Udupa

Papers

Cysteine complexes of palladium(II) and platinum(II)

Chromium(llI) Complexes of N-Salicylideneamino Acid

The crystal and molecular structure of thiocyanatobis(thiourea)silver(I)

Ethyl cysteinate complexes of palladium(II) and platinum(II)

Complexes of palladium(II) and platinum(II) with mercaptoacetic and 3-mercaptopropionic acids