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The coordination chemistry of the multidentate Schiff-base ligands 2,5-bis(3-methylpyrazinyl)-3,4-diaza-2,4-hexadiene (L5) and 2,5-bis(pyrazinyl)-3,4-diaza-2,4-hexadiene (L6) with inorganic Ag(I) salts is investigated. The bipyrazine-type ligands L5-L6 resulted in unusual building blocks due to their multidentate and chealting coordination behavior, leading to the construction of polymeric motifs that are achieved using bipyridine-type Schiff-base ligands L1-L4.

Silver(I) complexes of the bis(pyrazolyl)methane ligands Ph(sub 2)C(pz)(sub 2), PhCH(pz)(sub 2), and PhCH9(sub 2)CH(pz) was prepared in an attempt to explore how sterically hindered poly methane ligands influence the variable coordination geometries exhibited by silver(I) complexes, especially its ability to participate in cation (super...) pi interactions.

[C.sub.2]-symmetrical bis(oxazoline) ligands bearing pendant alkylthio ether groups were synthesized, and the structures of Cu complexes were determined by single crystal X-ray diffraction. The potential utility in catalysis was shown in the asymmetric addition of methyllithium to an aromatic aldimine, which resulted in a mixture of products with an enantiomeric excess of 68%. Key words: two-center catalysis, bis(oxazoline), aldimine, imine alkylation.

Steady state electronic absorption, fluorescence emission, polarized spectra of some disubstituted indoles were studied in solvents of different polarity coupled with time resolved measurements. The electrochemical measurements demonstrate that dimethylindoles (DMIs) should act as electron donors in photoinduced electron transfer (PET) reactions with 9Cyanoanthracene (9CNA).

The infrared and vis-near-IR spectra of the donor-acceptor chromophores 1-3 bearing thiophene-based spacers end-capped with 1,3-dithiol-2 ylidene and dicyanomethylene groups are investigated. The vibrational and electronic property of chromophores 1-3 compounds is largely influenced by the quinonoid structure of the bridge.

A study is conducted to examine the interaction of the ruthenium hybride complex CpRuH(CO)(PCy3) with proton donors HOR of different strength in hexane and is compared with data in dichloromethane. The protonation of a transition metal hydride appears as a complicated process in which hydride basicity, proton donor strength and secondary interactions among the acids and the bases present, and concentration effects are relevant.

Raman results are presented for Cu2O2 systems in which the spectroscopic features of the side-on peroxo-dicopper(II)/bis-mu-oxo-dicopper(III) equilibrium which are electronically, rather than sterically, controlled. The studies define the effects of endogenous donor strength on Cu-O and O-O bonds.

Various explanations for the torquoselelctivity of silylcyclobutene ring-openings are investigated theoretically. The role of sigma and sigma* orbitals in the ring-opening transition states is reported.

The synthesis and spectroscopic characterization of the mononuclear uranium(III) complex is reported. The coordination properties of the series of molecules provide interesting examples to illustrate the complexity of metal-ligand interactions found in uranium coordination chemistry.

Research has been conducted on C (sub)2 -chiral bisoxazine ligand. The first example of this ligand and its complexation to palladium(II) is reported.

Research has been conducted on 2-(phenylazo)pyridine ruthenium complex. The study of the aromatic ring amination reactions of this complex is presented.

Research has been conducted on bond valence sum. The problems in establishing R (sub)0 values for Ce complexes with O donors have been investigated, and the results demonstrate that these R (sub)0 values can be used for calculation of Ce oxidation state in complexes where Ce is bonded only to O ligands.

Research has been conducted on saccharide-based ferrichrome analogue. The coordination chemistry of this analogue has been investigated, and the results are reported.

Research has been conducted on trivalent hexaaquo- and hexaamminemetal ions. Results demonstrate that these ions can form fully encapsulated species, half-encapsulated complexes with divalent hexaaquo ions and related Jahn-Teller distorted complex.

Research discusses the isolation and characterization of osmium complexes that involve the Schiff base diimine ligand, N-arylpyridine-2-carboxaldimine. Results reveal that the diimine in the osmium(II) center coordinated N-arylpyridine-2-carboxaldimine ligand renders it susceptible to oxidation, leading to a z+1 metal oxidation state upon oxidation of one ligand.

Results reveal that coordination of the tripyridinedimethane ligand to a copper atom prevents planarization of py-CH(sub)2-py fragments of the ligand leading to the suppression of high acididity of the methylene bridges of the free ligand.

Research has been conducted on ligands N,N',N'-tetraacetate. The coordinating ability of these ligands toward lead(II) has been investigated via the use of potentiometry, UV-vis spectrophotometry and (super)207 Pb NMR spectroscopy, and the results are reported.

Research has been conducted on the de novo structure-based drug design in the field of coordination chemistry. The use of the Host-Designer software created to discover metal ion receptors and the analysis and use of the host-building and scoring algorithms are described.

Research has been conducted on the tetradentate ligand copper(II) and copper(I) complexes. The preparation and analysis of these complexes carried out spectroscopically, electrochemically and structurally are described.

Research demonstrates the highly selective addition of the bis(allyl)titanium complexes to alpha-imino esters to form (syn, E)-configured amino acids of different types and the synthesis of two new N-sulfonyl alpha-imino esters.

This study describes a novel method for improving the specific recognition, detection, and identification of proteins involved in multiprotein complexes. The method is based on a combination of coimmunoprecipitation, chemical cross-linking, and specific fluorescent tagging of protein components in close association with one another. Specific fluorescent tagging of the protein complex components was achieved using the cleavable, fluorescent cross-linker suffosuccinimidyl 2-(7-azido-4-methylcoumarin-3-acetamido) ethyl-1,3'-dithiopropionate (SAED). Following dissociation and separation by SDS-PAGE, the fluorescently tagged proteins are then visualized by UV illumination, excised, and, following in-gel digestion, identified by mass spectrometry. In this study, a complex of the HIV-envelope protein gp120 and its cellular receptor CD4 was used as a model system. The sensitivity of detection of fluorescent SAED-labeled proteins in SDS gels, and the sensitivity of the mass spectrometric identification of fluorescent proteins after in-gel digestion, is in the range of a few hundred femtomoles of protein. This sensitivity is comparable to that achieved with silver-staining techniques, but fluorescence detection is protein independent and no background interference occurs. Furthermore, fluorescence labeling is significantly more compatible with mass spectrometric identification of proteins than is silver staining. The first application of this strategy was in the investigation of the mechanism of spermiation, the process by which mature spermatids separate from Sertoli cells. For the coimmunoprecipitation experiment, an antibody against paxillin, a protein involved in spermatid-Sertoli cell junctional complexes, was used. More components of the paxillin protein complex were visible by fluorescence detection of SAED-labeled proteins than were visible on comparable silver-stained gels. Mass spectrometric analysis of the fluorescently labeled proteins identified integrin [[alpha].sub.6] precursor as a protein associated in a complex with paxillin. The identification of integrin [[alpha].sub.6] precursor was confirmed by Western blot analysis and verifies the applicability of this novel approach for identifying proteins involved in protein complexes.

The bridging ligands [L.sup.1] and [L.sup.2] contain two N,N-bidentate pyrazolyl-pyridine units linked to a central aromatic spacer unit (1,2-phenyl or 2,3-naphthyl, respectively). Reaction with Ni(II) salts and treatment with the anions tetrafluoroborate or perchiorate result in formation of dinuclear complexes having a 2:3 metal:ligand ratio, with one bridging and two terminal tetradentate ligands. In contrast, reaction of [L.sup.1] and [L.sup.2] with Co(II) salts, followed by treatment with tetrafluoroborate or perchlorate, results in assembly of cage complexes having a 4:6 metal:ligand ratio; these complexes have a metal ion at each corner of an approximate tetrahedron, and a bis-bidentate bridging ligand spanning each edge. The central cavity is occupied by a tetrahedral counterion that forms multiple hydrogen-bonding interactions with the methylene protons of the bridging ligands. The anionic guest fits tightly into the central cavity of the cage to which it is ideally complementary in terms of shape, size, and charge. Solution NMR experiments show that the central anion acts as a template for cage formation, with a mixture of Co(II) and the appropriate bridging ligand alone giving no assembly into a cage until the tetrahedral anion is added, at which point cage assembly is fast and quantitative. The difference between the structures of the complexes with Ni(II) and Co(II) illustrate how the uncoordinated anions can exert a profound influence on the course of the assembly process.

A molecular receptor consisting of a spacer bearing two cofacially disposed terpyridyl-palladium-ligand (terpy-Pd-L) units rigidly separated by about 7 [Angstrom] has been investigated for molecular recognition of planar aromatic molecules. It is found that although the receptor forms stable 1:2 host-guest association complexes with 9-methylanthracene (9-MA), the guest undergoes very rapid site exchange within the receptor and with external free 9-MA. A crystal structure of the 2:1 adduct shows one 9-MA in the molecular cleft defined by the two terpy-Pd-L units and the other resides on an outside face of one terpy-Pd-L unit. To establish the site residency time of the guests, a number of tethered molecules were prepared. These involve an anthracene molecule tethered to a pyridine ligand bound to the palladium atoms to form intramolecular host-guest adducts. Rotating-frame Overhauser effects were used to infer the site residency of the anthracene guests in the receptor. Variable-temperature [sup.1]H NMR spectroscopy of the intramolecular host-guest complexes has revealed that the site residency time of the anthracene guests is 1.6 x [10.sup.-5] sec at 20 [degrees] C and 1.3 sec at -90 [degrees] C in acetone solution. Whereas the guests are thermodynamically stable, they are kinetically very labile. A crystal structure of one of the tethered host-guest adducts reveals the expected structure which is the same as that determined in solution by [sup.1]H rotating-frame Overhauser enhancement spectroscopy experiments.

Research elucidates the electrophile-mediated intramolecular carbon-carbon bond-forming reactions of alkynyl/alkenyl/alkyl complexes of group 9 metals. Data show that alkynyl complexes containing iridium exhibit intramolecular carbon-carbon bond-forming reactions between alkynyl and hydrocarbyl ligands yielding conjugated olefins.

An identification procedure connected with selection of candidates for identification according to high values of their literature citation and cocitation is suggested. The citation rate of the compound is the number of different literature units, such as papers, patents, etc., recording its name. The cocitation rate is the number of such units mutually recording the names of two corresponding compounds or the compound and the sample/matrix. General citation of a chemical compound is assumed to be related to the prior probability of its being contained in a sample to be analyzed. This citation measures abundance and popularity of the compound. Cocitation of a compound with a known/identified constituent of a sample is related to their mutual similarity in structure or properties, origin, use, etc. This data processing method is validated by counting citations and cocitations for detected impurities in pure n-hexane and naphthalene, polycyclic aromatic hydrocarbons in waste gas, as compared with counts for similar or dissimilar compounds that are absent in the samples. The analytes are preidentified by combined gas chromatography and mass spectrometry techniques. A median and a mean value of citation and cocitation are always higher for the group of unambiguously identified compounds. A difference between identified and similar compounds in citations or cocitations may be rather insignificant, with combined evaluation of both indicators distinguishing these groups. Chemical dissimilarity results in a large difference in cocitation values.

The optically pure axially chiral chromium-complexed benzamides and anilides, derived from an asymmetric synthesis, are oxidized under air to obtain chromium-free compounds in an enantiometrically active form.

Research describes the synthesis of unique, homoleptic, trigonal bipyramidal cluster complexes by a strict self-assembly process involving the ligands poap and p3oap and the proper metal perchlorate salt.

Results demonstrate that catecholates and semiquinones can be synthesized from anthragallol, purpurin, and quinalizarin. Properties of ruthenium complexes of the polyhydroxy-9,10-anthracenediones purpurin, anthragallol, and quinalizarin are discussed.

The excitations in polyatomic molecules at wavelengths in the vicinity of the ground state to ground state excitation frequency may lead to significant cooling of the excited vibrational state distribution. This cooling effect will slow down the electron-transfer rate.

A new study shows that structural rigidity and preorganized guest binding sites have a strong influence on template efficiency when synthesizing hydrogen bond-assembled rotaxanes.

The ruthenium(II) complex, [Ru[Cl.sub.2](NO)L] (I), (L = [[(2-py).sub.2]P[C.sub.2][H.sub.4]P[O.sub.2](2-py)]-) was obtained from recrystallization of Ru[Cl.sub.3]NO(d2pype) (d2pype = [(2-py).sub.2]P[C.sub.2][H.sub.4]P[(2-py).sub.2]) in the presence of HN[O.sub.3], crystallizing in the monoclinic space group [P2.sub.1] (no. 4), with a = 8.012(4) [Angstrom], b = 14.454(4) [Angstrom], c = 9.353(3) [Angstrom], [beta] = 105.77(3)[degrees], and Z = 2. Crystals of the DMSO solvate of the complex (II) were obtained from [(C[D.sub.3]).sub.2]SO solution, crystallizing in the monoclinic space group [P2.sub.1]/c (no.14) with a = 9.7080(2) [Angstrom], b = 22.2920(5) [Angstrom], c = 11.5230(3) [Angstrom], [beta] = 92.0450(10)[degrees], and Z = 4. In both complexes, the geometry about the ruthenium atom is a distorted octahedron mainly as a result of the tridentate [P,N,O]-bonding mode of L. The v (NO) bands at 1875 [cm.sup-1] in both complexes are consistent with the linear disposition of the NO group and the Ru atom as is observed in the X-ray crystal structure (Ru-N1-O1 angle = 178.5(4)[degrees]). Key words: pyridylphosphine, nitrosyl, ruthenium complex, X-ray structure.

The 16[e.sup.-] bromo or iodo complexes [RuX[(dppp).sub.2]].sup.+] (dppp = 1,3-bis(diphenylphosphino)propane, X = Br (1c), I (1d)) and [[RuX[(dppe).sub.2]].sup.+] (dppe = 1,2-bis(diphenylphosphino)ethane, X = Br (2,c), I (2d)) have been prepared exploiting the reaction of the fluoro complexes [RuF[(dppp).sub.2]].sup.+] (1a) and [[Tl [([micro]-F).sub.2]Ru[(dppe).sub.2]].sup.+] (3) with activated alkyl bromides or iodides. The X-ray structures of 1c, 1d, 2c, and 2d suggest that the distortion of the Y-shaped trigonal-bipyramidal structure of [[MX([P.sup.[intersection]P).sub.2]]+ is possibly related to the formation of intramolecular hydrogen bonds between the halide ligand and the ortho-hydrogen atoms of the neighbouring phenyl rings. The five-coordinate species 1c, 1d, 2c, and 2d react with H2 to form the dihydrogen complexes [[RuX([[eta].sup.2]-[H.sub.2]) ([P.sup.[intersection]]P).sub.2]].sup.+]. The reaction of the dppp derivatives 1c and 1d with H2 (P = 1 atm, 1 atm = 101.322 kPa) is an equilibrium. Quantitative formation of [RuBr([[eta].sup.2]-[H.sub.2]) [(dppp).sub.2]] (4c) is obtained under [H.sub.2] pressure (100 bar, 1 bar = 100 kPa), whereas the iodo analogue is not stable under analogous conditions. The less crowded dppe derivatives 2c and 2d react quantitatively with H2 under ambient pressure. The iodo and bromo derivatives [[RuX([[eta].sup.2]-[H.sub.2]) ([P.sup.[intersection]]P).sub.2]].sup.+] contain elongated dihydrogen ligands, as indicated by their transverse relaxation times [T.sub.1] (min). The present data suggest that Cl, Br, and I have similar donor properties in these dihydrogen complexes, and that the different chemical behaviour in the C1, Br, I series is mainly a result of steric effects. Key words: 16[e.sup.-] complexes, ruthenium, fluoro complexes, bromo complexes, iodo complexes, dihydrogen complexes.

The mono(acetylacetonato) complexes [MCl(O,O'-acac) ([[eta].sup.6]-arene)] (M = Ru, Os, arene = [C.sub.6][H.sub.6], 1,3,5-[C.sub.6][H.sub.3][Me.sub.3], [C.sub.6][Me.sub.6]; M = Os, arene = 1,2-[C.sub.6][H.sub.3][Me.sub.2], 1,2,3-[C.sub.6][H.sub.3] [Me.sub.3]), which are formed from [[M[Cl.sub.2] ([[eta.sup.6]-arene)].sub.2] and thallium or sodium acetylacetonate, react with thallium acetylacetonate to give bis(acetylacetonato) complexes [M(O,O'-acac)([[eta].sup.1]-acac)([[eta].sup.6]-arene)]. The [[eta].sup.1]-acac ligand is bound through the [gamma]-carbon atom for M = Ru, Os, arene = [C.sub.6][H.sub.6]; M = Os, arene = 1,2-[C.sub.6][H.sub.4][Me.sub.2], 1,2,3-[C.sub.6][H.sub.3][Me.sub.3] and through a keto-oxygen atom for M = Ru, Os, arene = 1,3,5-[C.sub.6] [H.sub.3][Me.sub.3], [C.sub.6][Me.sub.6], the difference being attributed to a combination of steric and electronic effects. Cationic ruthenium(II) derivatives [Ru(L)(O,O'-acac)([[eta].sup.6]-arene]+ (arene = [C.sub.6][H.sub.6], 1,3,5-[C.sub.6][H.sub.3][Me.sub.3], [C.sub.6][Me.sub.6]; L = DMSO, MeCN, py, P[Ph.sub.3]) and [Ru(CO) (O,O-acac)([[eta].sup.6]-arene]+ (arene = 1,3,5-[C.sub.6][H.sub.3] [Me.sub.3],[C.sub.6][Me.sub.6]), and neutral osmium(II) [[eta].sup.1]-acetato derivatives [Os([[eta].sup.1]-OAc) (O,O'-acac) ([eta].sup.6]-arene)] (arene = [C.sub.6][H.sub.6], 1,2-[C.sub.6] [H.sub.4][Me.sub.2], 1,2,3-[C.sub.6][H.sub.3][Me.sub.3], 1,3, 5-[C.sub.6][H.sub.3][Me.sub.3], [C.sub.6][Me.sub.6]) are also described. The molecular structures of the following complexes have been determined by X-ray crystallography: [Os(O,O'-acac) ([[eta].sup.1]-C-acac)([[eta].sup.6]-1,2-[C.sub.6][H.sub.4] [Me.sub.2])], triclinic, space group P [bar]1 (No. 2), a = 9.922(2), b = 9.974(2), and c = 11.001(2) [Angstrom], [alpha] = 68.33(1), [beta] = 64.18(1), and [gamma] = 62.38(1)[degrees], V = 849.0(3) [Angstrom], Z = 2; [Os(O,O'-acac)([[eta].sup.1]-O-acac)([[eta].sup.6]-1,3, 5-[C.sub.6][H.sub.3][Me.sub.3])], monoclinic, space group C2/c (No. 15), a = 16.032(4), b = 11.989(3), and c = [2.sub.1].562(7) [Angstrom], [beta]= 108.91(2)[degrees], V = 3921(2) [Angstrom], Z = 8; [Os([[eta].sup.1]-OAc)(O,O'-acac)([[eta].sup.6]-[C.sub.6][H.sub.6])], triclinic, space group P [bar]1 (No. 2), a = 8.368(4), b = 8.402(4), and c = 11.008(4) [Angstrom], [alpha] = 71.68(3), [beta] = 69.35(3), and [gamma] = 69.77(3)[degrees], V = 663.0(6) [[Angstom].sup.3] Z = 2. Key words: arene-ruthenium, arene-osmium, acetylacetone, crystal structures.

The coordination chemistry of phenoxide ligands, such as [C.sub.6] [H.sub.5][O.sup.-], 4-(C[H.sub.3])-[C.sub.6][H.sub.4][O.sup.-], 3,5-[(C[H.sub.3]).sub.2]-[C.sub.6][H.sub.3][O.sup.-], 2,6-[(tert-butyl).sub.2]-[C.sub.6][H.sub.3][O.sup.-]-, 2,6-[(C[H.sub.3]).sub.2]-[C.sub.6][H.sub.3]0-, to Mn(II) has been investigated because of the possible implication of Mn(II)-phenoxide complexes as intermediates in the phenylphosphate carboxylase enzyme, a protein which catalyses the selective carboxylation of phenylphosphate to 4-OH-benzoic acid using C[O.sub.2]. We report here the synthesis and characterization of [[CpMn([[eta].sup.5]-OAr)(THF)].sub.2] (ArO = [C.sub.6][H.sub.5] [O.sup.-], 4-(C[H.sub.3])-[C.sub.6][H.sub.4][O.sup.-], 3,5-[(C[H.sub.3]).sub.2]-[C.sub.6][H.sub.3][O.sup.-], 2,6-[(C[H.sub.3]).sub.2]-[C.sub.6][H.sub.3][O.sup.-]) and [CpMn([[eta].sup.5]-ArO)] (ArO = 2,6-[(tert-butyl).sub.2]-[C.sub.6] [H.sub.3][O.sup.-] and 2,6-[(CH.sub.3]).sub.2]-[C.sub.6][H.sub.3] [O.sup.-]) complexes, the first examples of mixed-sandwich complexes with Cp and phenate as [pi]-ligands. The latter bear the 2,6-substituted phenoxide [pi]-coordinated to the [[Mn(Cp)].sup.+] moiety. The different mode of bonding of the phenoxide ligands to Mn(II), substantiated by [sup.1]H NMR and electron spin resonance (ESR) spectroscopy, is controlled by the steric hindrance of substituents at the 2- and 6-position. The reactivity of the [pi]-bonded ligand towards C[O.sub.2] is also reported as a quite rare example of nucleophilic attack at the cumulene by the ring-carbon of the phenoxide, which is driven by electron density localization at the 4-position generated upon [pi]-coordination to Mn(II). Key words: Mn(II)-complexes, phenoxide ligands, [sup.1]H NMR spectroscopy, ESR spectroscopy, reaction with carbon dioxide.

The synthesis of the cationic hydridotris(pyrazolyl)borate iridium(III) complex [Tp(P[Me.sub.3])IrMe(ClC[H.sub.2]Cl)][[BAr.sub.f]] (2-C[H.sub.2][Cl.sub.2]) is reported. Spectroscopic characterization of 2-C[H.sub.2][Cl.sub.2] in C[H.sub.2][Cl.sub.2] solution indicates that exchange of bound C[H.sub.2][Cl.sub.2] with free C[H.sub.2][Cl.sub.2] is slow on the NMR time scale. Under 50 atm (1 atm = 101.325 kPa) of [N.sub.2], the C[H.sub.2][Cl.sub.2] in 2-C[H.sub.2][Cl.sub.2] is displaced by [N.sub.2] to yield [Tp(P[Me.sub.3])IrMe(N2)][[BAr.sub.f]] (2-[N.sub.2]). The stronger nucleophile C[H.sub.3]CN reacts rapidly with 2-C[H.sub.2][Cl.sub.2] to produce [Tp(PMe3)IrMe(NCCH3)][BArf] (4). A kinetic study was performed on C[H.sub.2][C1.sub.2] substitution in 2-C[H.sub.2][Cl.sub.2] by C[D.sub.3]CN. The data are most consistent with dissociative loss of C[H.sub.2][C1.sub.2] to generate the unsaturated species ([Tp(P[Me.sub.3])IrMe][[BAr.sub.f]]) which then reacts with C[D.sub.3]CN to generate [Tp(P[Me.sub.3]) IrMe(NCC[D.sub.3])] [[BAr.sub.f]]. Further evidence for a dissociative mechanism was obtained by comparison of ligand substitution rates for the Tp complexes with the analogous [Tp.sup.Me2] complexes ([Tp.sup.Me2] = hydridotris(3,5-dimethylpyrazolyl)borate). The relevance of these substitution experiments to C--H activation by cationic iridium(III) complexes is discussed. Key words: iridium, hydridotris(pyrazolyl)borate, methylene chloride and dinitrogen complexes, dissociative substitution.

The chelate complex [Ru[Cl.sub.2][{[kappa].sup.2](P,O)-i-[Pr.sub.2] PC[H.sub.2]C[H.sub.2]OMe}.sub.2]] (1) reacted, in the presence of C[F.sub.3]S[O.sub.3]Ag, with 1 equiv of [C.sub.6][H.sub.4]([C [equivalent to] CH).sub.2.sup.-p] (4) to afford the mononuclear vinylidene compound [RuCl(C=CH[C.sub.6][H.sub.4.sup.-p-]C [equivalent to]CH) {[[kappa].sup.2](P,O)-i-[Pr.sub.2]PC[H.sub.2] C[H.sub.2]OMe}.sub.2]](C[F.sub.3]S[O.sub.3] (3). From 1 and 0.5 equiv of 4, the binuclear bis(vinylidene) complex [RuCl{[[kappa].sup.2] (P,O)-i-[Pr.sub.2]PC[H.sub.2]C[H.sub.2]OMe}.sub.2]](C=CH[C.sub.6] [H.sub.4.sup.-p-]CH=C)RuCl{[[kappa].sup.2](P,O)-i-[Pr.sub.2]PC[H.sub.2] C[H.sub.2]O[Me.}.sub.2]((C=H[C.sub.6][H.sub.4.sup.-p]CH=C) RuCl{[[kappa].sup.2](P,O)-i-[Pr.sub.2]PC[H.sub.2]C[H.sub.2]OMe}.sub.2]] ((C[F.sub.3]S[O.sub.3]).sub.2]] (6) was obtained. The related compound [[RuCl{[[kappa].sup.2](P,O)-i-[Pr.sub.2]PC[H.sub.2] C[H.sub.2]OMe}.sub.2]] (C=CH[C.sub.6][H.sub.4.sup.-m]CH=C)RuCl {[[kappa].sup.2](P,O)-i-[Pr.sub.2]PC[H.sub.2]C[H.sub.2]OMe}.sub.2]] (C[F.sub.3]S[O.sub.3]).sub.2] (7) was prepared from 1, 0.5 equiv of [[C.sub.6][H.sub.4](C [equivalent to] CH).sub.2.sup.-m]] (5), and silver triflate. The reaction of 2 or 3 with [[RhCl(P-i-[Pr.sub.3]).sub.2]2]] (8) in the molar ratio of 2:1 yields, by addition of the 14-electron fragment [[RhCl(P-i-[Pr.sub.3]).sub.2]2]] to the uncoordinated C--C triple bond, the heterobinuclear complexes [RuCl{[[kappa].sup.2](P,O)-i-[Pr.sub.2] PC[H.sub.2]C[H.sub.2]OMe}.sub.2](C=CH[C.sub.6][H.sub.4.sup.-m/p] C [equivalent to] CH)[[RhCl(P-i-[Pr.sub.3]).sub.2]2]][(C[F.sub.3] S[O.sub.3]) (9, 10) which slowly rearrange at room temperature to give the bis(vinylidene) isomers [RuCl{[[kappa].sup.2](P,O)-i-[Pr.sub.2] PC[H.sub.2]C[H.sub.2]OMe}.sub.2](C=CH[C.sub.6][H.sub.4.sup.-m/p]CH=C) RuCl(P-i-[Pr.sub.3]).sub.2]2](C[F.sub.3]S[O.sub.3]) (11, 12). Key words: ruthenium, rhodium, vinylidene complexes, alkyne complexes, phosphine complexes.

Catalysts were prepared by adsorbing [Rh.sub.2][Cl.sub.2][(CO).sub.4] directly on gold powder or on gold that contained the tethered ligands 2-(diphenylphosphino)ethane-1-thiol (DPET) or methyl 2-mercaptonicotinate (MMNT). Infrared (IR) studies (diffuse reflectance infrared Fourier transform (DRIFT)) of the catalyst Rh--Au prepared by adsorbing [Rh.sub.2][Cl.sub.2][(CO).sub.4] directly on Au indicate that a [Rh.sup.I][(CO).sub.2] species is present. IR studies of Rh--DPET-Au suggest that tethered cis-Rh(DPET)[(CO).sub.2]Cl is the major species at relatively high [Rh.sub.2][Cl.sub.2][(CO).sub.4] loadings, but trans-Rh[(DPET).sub.2](CO)Cl is observable at low [Rh.sub.2][Cl.sub.2] [(CO).sub.4] loadings. Spectral investigations of the catalyst Rh-MMNT-Au prepared by adsorbing [Rh.sub.2][Cl.sub.2][(CO).sub.4] on MMNT-Au suggest that tethered [[cis-Rh[(MMNT).sub.2] [(CO).sub.2]].sup.+][Cl.sup.-] and (or) Rh(MMNT)[(CO).sub.2]Cl are the major species at low [Rh.sub.2][Cl.sub.2][(CO).sub.4] loadings, while a new unidentified species predominates at high [Rh.sub.2][Cl.sub.2] [(CO).sub.4] loadings. All three catalysts are active 1-hexene hydrogenation catalysts under the mild conditions of 40[degrees]C and 1 atm of [H.sub.2]; they are much more active than Au powder or [Rh.sub.2][Cl.sub.2][(CO).sub.4] in solution. Of the three catalysts, Rh--Au is the most active with a maximum turnover frequency (TOF) of 800 mol [H.sub.2] per mol Rh per min while its turnover (TO) is 29 600 mol [H.sub.2] per mol Rh during a 2-hour run. Under the conditions of 1-hexene hydrogenation, the catalysts lose their CO ligands. Thus, it appears that a form of Rh metal on Au is the catalytically active species. Key words: catalysis, olefin hydrogenation, gold powder, tethered rhodium complexes, infrared studies, adsorption, rhodium complexes.

The synthesis of four double-chain surfactant cobalt(III)complex pairs is described. Results show that the compounds are mostly insoluble in water and their use as surfactants is very limited. However, the ratio of diastereomer increases from ethanol-water to water due to hydrophobic effect of N-alkylethylenediamine ligand aggregation in water.

Research is presented describing the use of dilute solution to measure the homopolymer chains of water/methanol complexation.

Synthesis of 3,3-bis(diphenylphospino)-1,1'-dimethyl-2,2`biindole (N-Me-2-BINP) and 3,3-bis(diphenylphospino)-1,1'-bis(methoxymethyl)-2,2`-biindole (N-Me-2-BINP) is investigated. Reactions were found to be fast and enantioselection quite good.

Application of the variable oxygen probe to low-temperature crystal data from the series of oxygenated anthracene cycloadducts, revealed strong response of the C-OR bond distance in these structures to the electron demand of the OR group. It is believed that this represents the manifestation of pi-sigma negative homohyperconjugation in the ground state.

A study of the ligand 4,5-bis(diphenylphosphino)-sym-octahydroacridine N,P,P'-trioxide (10) which is obtained from a multistep synthesis and characterized by spectroscopic methods, and two crystal forms are examined by single-crystal x-ray diffraction techniques. The results show that the molecules form chains along the z-axis in which the ligand bonds in a bidentate mode to one La(NO3)(sub 3) or Nd(NO3)(sub 3) by using the N-O and one of the P=O donor centers.

Research demonstrates a four-step synthetic strategy for preparing germyl linker useful to immobilize lithiated aromatic derivatives onto Argogel resin. Data show that using this methodology a library of pyrazoles can be prepared from acetophenone-functionalized resins.

A new study investigates the use of 4-substituted-2-(2-diphenylphosphinophenyl)oxazolines as chiral ligands for alkyne-dicobaltcarbonyl complexes.

Research is presented into the complexation of B-chlorodiisopinocampheylborane.

This paper discusses the usefulness of the chemistry of transition-metal-mediated dearomatization in the synthesis of complex organic compounds with high regio-, chemo-, stereo-, and enantioselectively. Dearomatization methodology for arene complexes of chromium, manganese, and osmium are described.

An analysis of the structure of a synthesized Prussian blue analogue using x-ray absorption spectroscopy is discussed. The results which increase our knowledge of the photoinduced electron transfer are presented.

Prussian blue compounds were synthesized to study the effect of photoinduced magnetization. The resulting structures with varying amounts of cobalt were examined and are presented.

Ruthenium alkylidenes which are water-soluble are synthesized, identified and studied. Their use in initiating olefin metathesis when in protic solvents is presented.

TcO(sub 2)F(sub 3) and ReO(sub 2)F(sub 3), both are fluoride ion donors towards AsF(sub 5) and SbF-(sub 5) leading to the formation of stable fluorine-bridged MO(sub 2)F(sub 3).PnF(sub 5) adducts (M = Te, Re; Pn = As, Sb) in the solid state and solvated MO(sub 2)F(sub 2)(super +) cations in HF and SbF(sub 2) solvents. The ReO(sub 2)F(sub 3).SbF(sub 5) adduct ionizes in CH(sub 3)CN and SO(sub 2)CIF solvents to form the cis-ReO(sub 2)F(sub 2)(CH(sub 3)CN(sub 2)(super +) and fluoride-bridged Re(sub 2)O(sub 4)F(sub 5)(super +) cations, respectively.