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Seven novel adducts of ethylenediamine (en), N,N′-dimethylethylenediamine (dmen) and N,N-dimethylethylenediamine (ndmen) with saccharinate, orotate and salicylate as counter-ions were synthesized and characterized with physico-chemical methods (IR and UV/vis spectroscopy, magnetic susceptibility and thermoanalytical measurements) and X-ray diffraction. Reaction of dmen with tetraaquabis(saccharinato-N)copper(II) dihydrate yielded diaquabis(dmen)copper(II) saccharinate, whereas with the corresponding nickel derivative it afforded bis(dmen)bis(saccharinato-O)nickel(II). In the copper complex the coordinated water and the primary nitrogen end of the donor ligand interact with the saccharinate anion [O1w⋯O3=2.833(2), N1⋯N2=2.992(2) A˚]. Adjacent molecules are linked by two more hydrogen bonds into a layer structure. In the nickel compound, the dmen ligand also chelates the metal atom, which is bonded to the carbonyl oxygen of the anionic group. The negatively-charged nitrogen atom of the anion is intramolecularly linked to the dmen [N1⋯N2=2.968(2) A˚]; hydrogen bonds link the molecules into layers. Under mildly basic conditions, the reaction of orotic acid with cobalt(II) afforded tetraaqua(2,6-dioxo-1,2,6-trihydropyrimidine-4-carboxylato-N,O)cobalt(II) hydrate. The complex was oxidatively reacted with en to give a mixed-ligand cobalt(III) adduct which includes both mono- and bisdeprotonated orotate ions. The metal atom in tetraaqua(2,6-dioxo-1,2,6-trihydropyrimidine-4-carboxylato-N,O)cobalt(II) hydrate is chelated by the orotato dianion through the carboxyl oxygen and 3-pyrimidyl nitrogen atoms, and its octahedral geometry is completed by four water molecules. The 1-pyrimidyl nitrogen atom engages in hydrogen bonding with the lattice water molecule. The cobalt atom is similarly chelated by the orotato dianion in bis(en)(2,6-dioxo-1,2,6-trihydropyrimidine-4-carboxylato-N,O)cobalt(III) 2,6-dioxo-1,2,3,6-tetrahydropyridimidine-4-carboxylate pentahydrate. The copper atom in the five-coordinate aqua(en)orotatocopper(II) monohydrate is chelated by the en ligand, the deprotonated N1 pyrimidine atom and the orotate carboxylate oxygen; the water molecule completes the square-pyramidal coordination. The nickel and copper atoms in bis(en)bis(salicylato-O)nickel(II) and bis(ndmen)bis(salicylato-O)copper(II) monomeric octahedral complexes are coordinated by the salicylato monoanion through the carboxylate oxygen in a monodentate fashion and by the en and ndmen molecules through the two amine nitrogen atoms in a bidentate chelating manner. In the copper complex, the carboxylate oxygen atom engages in hydrogen bonding with the lattice water molecule. [Copyright &y& Elsevier]

A novel rare-earth metal(III) saccharinate, namely bis(o-sulfobenzimidato)praseodymium(III) chloride hexahydrate, is synthesized and its solid-state structure is suggested from the FT IR and UV/vis spectroscopic, thermoanalytical, elemental and magnetic measurements. The OH, CO, SO2 and OD stretchings (the latter isolated in H2O matrix) in the FT mid-infrared spectra of the frozen protiated and partially deuterated analogues of the complex spectra-structural correlations in other saccharinates to predict the structure of the o-sulfobenzimidate residues and the hydration water. The structure features a single crystallographic type of O-coordinated or ionic saccharinato residues, with at least three structural types of water of hydration, and chloride counter-ions in the outer-sphere. [Copyright &y& Elsevier]

Some new substituted cyclotriphosphazenes were prepared by the reaction of hexachlorocyclotriphosphazene and 3-allyl-4-hydroxyazo compounds such as 3-allyl-4-hydroxyazobenzene, 4′-chloro-3-allyl-4-hydroxyazobenzene, 4′-methyl-3-allyl-4-hydroxyazobenzene, 4′-bromo-3-allyl-4-hydroxyazobenzene, 4′-acetyl-3-allyl-4-hydroxyazobenzene, 3′,4′-dimethyl-3-allyl-4-hydroxyazobenzene and 4′-iodo-3-allyl-4-hydroxyazobenzene. They are characterized by UV–VIS, FT-IR, 1H-NMR, 13C-NMR, elemental analysis, TG, DTG and DTA. [Copyright &y& Elsevier]

The asymmetric unit of the title compound, C5 H7 N2O+ ·C4 H4NO4S-, contains one cation and one anion. The 6-methyl-2,2,4-trioxo-2H,4H-1,2,3-oxathiazin-3- ide anion adopts an envelope conformation with the S atom as the flap. In the crystal, the anions and cations are held together by N--H…O, N--H…N, O-- H…O and C--H…O hydrogen bonds, thus forming a three-dimensional structure. The Hirshfeld surface analysis and fingerprint plots reveal that the crystal packing is dominated by O…H/H…O (43.1%) and H…H (24.2%) contacts. [ABSTRACT FROM AUTHOR]

Analytical filter papers are generally made of fibrous cellulose which has the potential to adsorb metal ions. In this study, blue band ashless filter paper was used to demonstrate one of the sources of error in the determination of the concentration of Fe2+, Co2+, Mn2+, Cd2+, Cu2+, Pb2+ and Zn2+ ions. For this purpose, the metal ion content of standard solutions in the 1-100 mg/l concentration range was analysed via FAAS before and after the filtration process. The corresponding results and the calculated percentage errors due to adsorption are presented. The effect of pH on the adsorption process was also investigated. Activated carbon and soil samples were spiked with each metal ion and the solid phases from the resulting solutions were separated by both filter paper methods and centrifugation. In the statistical estimation of the results, the paired t-test was applied for non-filtered and filtered solutions in the concentration range 1-100 mg/l using the data analysis tools available in MS Excel®. The use of filter paper caused systematic errors, particularly at lower metal concentrations, and hence centrifugation or a filtering process using techniques other than filter paper is favoured as a better approach towards estimating the concentration of heavy metal ions from aqueous solution. [ABSTRACT FROM AUTHOR]

Determines the structures of dinicotinamidium squarate. Crystal structure; Chemical composition; Molecular structure.