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A dinuclear metal complex is bound tightly and selectively to oxalate over other dicarboxylates. Crystal structure of oxalate bound to the receptor together with molecular mechanisms and density functional theory (DFT) computations have helped in understanding the tight and selective building of the anion by the receptor.

The article discusses a new approach, where in the stereoselective thermodynamic and kinetic processes are employed for the reactive extraction of different enantiomers of 1,2-amino alcohols. The extraction process is shown to be extremely effective, time-saving and cheap.

Development of a chiral analogue of pyridoxal that binds amino acids by formation of imines with resonance-assisted H-bonds (RAHBs) is reported. The strong H-bonds could be used to activate the bound amino acids and convert L-amino acids to D-amino acids by epimerization of the imines formed between chiral analogue and L-amino acids.

A new fluorescent sensor based on rhodamine B for Pb(super 2+) was synthesized. The new fluorescent sensor showed an extreme selectivity for Pb(super 2+) over other metal ions examined in acetonitrile.

Research has been conducted on one-, two- and three-dimensional coordination polymers. The preparation of these polymers by binary metal comples systems' self-assembly in aqueous solutions is described.

The synthesis, separation and characterization of the isomers of the mixed carboxylatoplatinum(IV) complexes are reported. The analysis shows that the positions of electrophilic substitution of (dach)Pt(OH)(sub 4) were influenced by the kinds of carboxylic anhydrides exhibiting different electrophilicity or steric effects.

A study showed the reversible recognition properties of the external space of [[[(dach)Pt(dteym)2Cu]2](super +) where two (dach) groups stand perpendicularly to and around the metal coordination plane. It also showed that a novel supramolecular system is generated through a double self-assembly using the pyridine recognition property.

Barium 1,3-dithiepan-2-ylidenemalonate exhibits a nine coordinate geometry consisting of three distinct carboxylate bonding modes in a two-dimensional indefinite structure. The indefinite structure originates from intermetallic coordination of the 1,3-dithiepan-2-ylidenemalonate ligand. Both the faces of the barium-oxygen plate contain an organic group of the seven-membered dithioether ring. The neighboring geometry of the barium atom suffers a distortion due to between-layer interactions.

One-dimensional (1-D), two-dimensional (2-D), and three-dimensional (3-D) coordination polymers were prepared by self-assembly of binary metal complex systems, copper(II) nitrate and (en)Pt[sup II](nic)[sub 2] or (dmpda)Pt[sup II](isonic)[sub 2] (en = ethylenediamine, dmpda = 2,2'-dimethyl-1,3-propanediamine, nic = nicotinate, and isonic = isonicotinate), in aqueous solutions. Equimolar reactions of copper(II) nitrate with (dmpda)Pt[sup II](isonic)[sub 2] and (en)Pt[sup II](nic)[sub 2] resulted in 1-D {[(dmpda)Pt(isonic)[sub 2]Cu(OH[sub 2])[sub 3]](NO[sub 3])[sub 2]}[sub n] (1) and 2-D {[(en)Pt(nic)[sub 2]Cu(OH[sub 2])](NO[sub 3])[sub 2]}[sub n] (2), respectively, but the reaction of (en)Pt[sup II](nic)[sub 2] with excess copper(II) nitrate gave 3-D {[((en)Pt(nic)[sub 2])[sub 3]Cu[sub 5](OH)[sub 2](OH[sub 2])[sub 6]](NO[sub 3])[sub 8]}[sub n] (3). The local structure of crystal 1 has a mononuclear copper unit, 2 has a dinuclear copper unit with a Cu-Cu distance of 2.659(5) Å, and 3 has a pentanuclear copper unit. The methyl groups of the dmpda ligand are located in the space between two isonicotinate ligands of 1, which is presumed to be an important factor to determine the final structure of the crystal formed by self-assembly. Magnetic behaviors of crystals 1-3 examined in the temperature range of 4-300 K appear to be governed by the local structures around the copper(II) ions and do not indicate any significant long-range magnetic exchange interactions along the polymeric chain. [ABSTRACT FROM AUTHOR]

Demonstrates the synthesis of a novel series of (diamine)platinum(IV) complexes of mixed carboxylates via electrophilic substitution of the tetrahydroxoplatinum(IV) complex with three different carboxylic anyhydrides, pivalic, acetic and trifluoroacetic anhydrides. Influence of carboxylic anhydrides; Lipophilicity of the compounds.

Examines a conceptual nanotubular sheet constructed by interweaving two independent undulating networks along with its anion exchangeability and thermal behaviors. X-ray characterization on a single crystal; Skeletal structure of the network; Decomposition in the temperature range.

A new fluorescent sensor based on rhodamine B for Pb2+ was synthesized. The new fluorescent sensor showed an extreme selectivity for Pb2+ over other metal ions examined in acetonitrile. Upon the addition of Pb2+, an overall emission change of 100-fold was observed, and the selectivity was calculated to be 200 times that of Zn2+. The signal transduction occurs via of reversible CHEF (chelation-enhanced fluorescence) with this inherent quenching metal ion. [ABSTRACT FROM AUTHOR]