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The synthesis and characterization of tri- and tetranuclear Cu(II) complexes utilizing mononuclear Cu(II) chiral building block with the sugar-derived Schiff's base ligand H3L(super 1) are reported. The results help in creating an efficient method for constructing chiral multinuclear complexes by utilizing the mononuclear {Cu(HL(super 1))} chiral building blocks.

Research has been conducted on the 1,3-propanadiamine derivatives connected to carbohydrates and prepared from peracetylated sugar and 1,3-dibromo-2-propanol. Anomeric configurations and sugar puckering conformations have been investigated via X-ray crystallography of diazido precursors.

Research has been conducted on the heptadentate N-glycoside ligand mononuclear manganese(II) complexes. The use of X-ray crystallography has been described.

Carbohydrates are widely occurring and are needed by living organisms. Naturally rare carbohydrates are involved in glycoproteins, glycolipids and antibiotics. The syntheses and structural determinations of novel seven-coordinated cage-type cobalt(II) compounds, containing N-glycosides from mannose-type aldoses is reported.

Incorporation of a monovalent group 11 metal ion (Au(I), Ag(I) or CU(I)) with d10 configuration into the Pt2 core has led to the formation of heterotrimetallic Pt2M complexes. The PtCuX assembly forms a rhombic structure when CuX fragment was introduced. The reactions could help in the synthesis of other heterotrinuclear complexes. The angle of Pt...Cu-X is less than 90 degrees resulting in a short interatomic distance between the terminal Pt and X atoms.

The synthesis and characterization of carboxylate-bridged dimagnesium(II) complexes containing the dinucleating XDK ligand where H2XDK = m-xylylenediamine bis(Kemp's triacid imide) were carried out. Consequently,, carboxylate- and phosphodiester-bridged dimagnesium(II)-XDK, dicalcium(II)-XDK and dizinc(II)-XDK complexes were prepared and found to be catalysts in the cleavage of phosphate ester bonds.

The reaction of (RuCl2(dmso)4) with dhptaH5 (1,3-diamino-2-hydroxypropane tetraacetic acid) and carboxylate ligands afforded diruthenium(III) complexes, M(Ru(dhpta)(mu-O2Cr)2). The complexes arer soluble and retain the dinuclear structure in water. They thus offer a good basis for clarifying redox properties of the diruthenium center. X-ray crystallography and EXAFS analysis were used to characterize the complexes.

Aldoses are coordinated on nickel(II) ion using the N-glycosidic bond formation with tris(2-aminoethyl)amine (tren). Specifically, mono-, bis- and tris-(sugar)complexes are synthesized and characterized. For example, (Ni tren H2O2)X2, where X = Cl, Br and X2 = SO4, reacts with mannose-type aldoses of 2,3-cis configuration (D-mannose and L-rhamnose) to yield bis(N-aldosyl-2-aminoethyl)(2-aminoethyl)amine nickel(II) complexes (Ni N,N'-aldosyl sub 2-tren)X2. The resulting complexes are characterized by X-ray analyses.

The reactions of linear trinuclear platinum complexes with small organic molecules yields asymmetrical A-frame triplatinum complexes. The complexes possess an extra bridge across one of the metal-metal bonds. The trinuclear complexes serve as models for the study of the interactions between small molecules and the surfaces of heterogeneous catalysts. The reactions of a linear triplatinum complex with electron deficient HBF4.Et2O and p-NO2C6H4NC are discussed.

The addition of Zn(acac)2.2H2O to [Zn(XDK)(H2O)] XDK mononuclear zinc complex will produce the dizinc compound [Zn2(XDK)(acac)2(CH3OH)2]. [Zn2(XDK)(acac)2(CH3OH)2] has four discrete molecules in its unit cells intermolecular contacts. [Zn(XDK)(H2O)] acts as a precursor to zinc-containing carboxylate-bridged heterodimetallic complexes. The Zn to M distance is linearly coordinated with the ionic radius of high-spin octahedral M ions. Carboxylate-bridged divalent heterodinuclear compounds acts models for heterodimetallic centers in nonredox metalloenzymes.

Dinuclear manganese(II) complex, Mn2(XDK)(NO3)(CH3OH)4(H2O2)NO3 can be synthesized by reacting Mn(NO3)2*6H2O with Na2XDK.4H2O. X-ray crystallographic analysis reveals that the cation in the resulting compound contains two octahedral Mn(II) ions attached by two molecules and a nitrate ion. Compound 1 exist in three oxidation states and is suitable for the synthesis of various bis(mu-carboxylato)dimanganese (II) complexes with N-donor bidentate terminal ligand. Synthesis of bis(mu-carboxylato)dimanganese (II) complexes is discussed.

The reaction between Zn(NO3)2.6H2O, H2XDK and NaOH yields the mononuclear zinc complex (Zn{XDK}{H2O}), which on further reaction with Zn(acac)2.2H20 leads to the asymmetrical dinuclear complex (Zn2{XDK}{acac}2{CH3OH}2).H2O. A dizinc structure bridged by XDK and acac ligands is detected, where the zinc atoms have a trigonal bipyramidal and octahedral geometry. The dizinc complex (Zn2{XDK}{NO3}2{CH3OH}{H2O}2) obtained from 1 reacts with phosphate ester salts to give the phosphate-bridged dinuclear zinc complexes.

An incomplete cubane-type cluster reacted with Pd black in aqueous HCl to yield a mixed-metal cubane-type cluster having a novel PdMO3S4 core. The structural properties and synthesis of these compounds were studied as models of active sites in biological catalysts. Mixed-metal sulfur clusters containing noble metals promoted stoichiometric and catalytic reactions.

The reaction of benzoic PdCl2(RNC)2 solution, where R is 2,6-Me2C6H3, with K(C5Ph5) followed by residual extraction alumina chromatography elution and hexane addition yields the binuclear Pd(I) isocyanide complex, Pd2(eta-5-C5Ph5)2(mu-2, 6-Me2C6H3NC)2.1.5 C6H6 in violet crystalline form. The Pd(I) complex and other such Pd(I) isocyanide complexes have weak Pd-Pd bond interactions due to full sigma and pi orbital occupancy in the dimer. The Pd-Pd bond distances are in the range 2.632 to 2.757 angstroms.

Diphosphine (diphos), aromatic isocyanide (RNC) and NH4PF6 reacted with PdCl2 (COD) to produce RNC and diphos ligands in monocellular palladium(II) complexes. A binuclear palladium(I) complex was derived from a controlled-potential electrolysis of the diphos ligand complexes at a platinum-plate electrode-consumed 1 F per mol in acetonitrile -1.6 V. Electronic, IR and H and P(H) NMR spectroscopies, X-ray crystallography and extended X-ray absorption five structure (EXAFS) were used to determine the properties of the binuclear palladium(I) complex.

The spontaneous adsorption and fixation of CO2 in air through the Ni(II) ethanol gives the trinuclear nickel(II) complex /Ni3(N,N-Me2en)6(CO3)(H2O)4~(ClO4)4. The trinuclear complex has a structure a = 25.824(7) Angstrom (A), c = 14.506(3) A, Z = 6 and space group P6(sub 3). It consists of three octahedral nickel(II) complexes connected by hydrogen bonds around the carbonate ligand. This bonding system may result in the spontaneous fixation of CO2 in air.

The novel tetranuclear copper(II) complexes with alpha-D-glucose-1-phosphates, [Cu(sub 4)(mu-OH)(alpha-D-Glc-1P)(sub 2)(L)(sub 4)(H2O)2(sub 2)](NO3)(sub 3) were prepared and characterized by X-ray crystallography. Complex [Cu(sub 4)(mu-OH)(alpha-D-Glc-1P)(sub 2)(L)(sub 4)(H2O)2(sub 2)](NO3)(sub 3) was revealed to be a good precursor of the adenosine 5'-triphosphate (ATP) stabilized tetranuclear Cu(super II) complex of [Cu4(ATP)2(bpy)4].

The synthesis and characterization for a D-Glc-1P-bridged tetranuclear copper(II) complexes, [[Cu4(mu-OH){mu-(alpha-D-Gle-1P)}2(L)4(H2O)2].sup.3+] and its Cu4 core transformation through incorporation of a series of sugar acids is presented. These complexes are revealed to incorporate a series of sugar acids through the Cu4 core structural changes, affording the sugar-coated rectangular Cu4 clusters and linearly ordered chiral coordination polymers.

A synthesis of biscarboxylate-bridged dicopper(II) complexes containing a series of sugar phosphate esters by utilizing the biscarboxylate ligand XDK (H(sub 2)XDK=m-xylenediamine bis(Kemp's triacid imide)) and imine-based chelating ligands is studied. The XDK has proved to be an efficient dinucleating ligand in stabilizing a variety of dinuclear metal centers.

The homo- and heterotrimetallic Zn(II) and Cu(II) complexes, [M(sub 2)M'{(D-Glc)(sub 2)-tacn}(sub 2)(XDK)]Cl(sub 2), prepared by stepwise construction from the D-glucose-binding mononuclear complexes, and [M{(D-Glc)(sub 2)-tacn}Cl]Cl, where tacn is 1,4,7-triazacyclononane is reported. These structures are useful substrate binding models of xylose or glucose isomerases, which promote D-glucose D-fructose isomerization by using divalent dimetallic centers bridged by a glutamate residue.

Three carboxylate- and phosphodiester-bridged dimagnesium(II) complexes are prepared which contain the dinucleating ligand XDK where H2XDK is m-xylenediamine bis(Kemp's triacid imide) and can model enzyme active sites for phosphate ester hydrolysis. The complex Mg2(XDK)(CH3OH)4(H2O)2(NO3) (NO3) has a carboxylate-bridged dinuclear magnesium(II) center. In Mg2(XDK)(DPP)(CH3OH)3(H2O)(NO3).3CH3OH where HDPP is diphenyl phosphate, both bridging and terminal diphenyl phosphate ligands are present.

The synthetic methodology for the preparation of carboxylate-bridged heterodimetallic complexes involves the use of dinucleating carboxylating ligand XDK, where H2XDK is m-xylenediamine bis(Kemp's triacid imide). XDK helps stabilize the carboxylate-bridged heterodimetallics. Formation of heterodimetallic complexes of the type (CoM(XDK)(neocuproine)(X)) by a reaction between alkalic metallic salt and a mononuclear Co(II) complex and (Co(XDK)(neocuproine)) reveals the efficiency of XDK in assembling heterodimetallic complexes.

The action of CoX2.6H2O on a methanol solution of D-mannose or L-rhamnose and tris(2-aminoethyl)amine yields unique seven-coordinated N-glycoside-containing cobalt complexes. The cobalt complexes containing halogenic anions have reversed configurations to the complexes containing a sulfate anion. The inversion occurs due to a complete reversal of configuration around the metal center. The complexes reveal a helical C3 geometry.

Studies on the reactivities of the incomplete cubane-type cluster (Mo3S4(H2O)9)4+ show that it is a highly potential precursor for synthesizing mixed-metal sulfido clusters with a cuboidal Mo3MS4 core. Single and double cubane-type clusters with a Mo3PdS4 core derived from (Mo3S4(H2O)9)4+ were synthesized and characterized. (Mo3S4(H2O)8)4+ coordinates an alkene ligand to the unique palladium site surrounded by sulfido ligands.

Peroxo-bridged dinuclear cobalt(III) complexes, [{Co((D-Glc)2-tren)}2(mu-O2)]X3.5H2O(X=Cl(2.5H2), Br (3.5H2O)) and [{Co((Mal)2-tren)}2(mu-O2)](Cl3.6H2)(4.6H2O), were derived from tris(2-aminoethyl)amine and D-glucose or maltose. Data gathered by ultraviolet-vis absorption, circular dichromism, H and C nuclear magnetic resonance spectroscopic methods and elemental, X-ray and crystallographic analyses indicate that the complexes being investigated have a tretravalent sugar domain around the dinuclear center.