Lactic acid metal complexes

Pranfois, C., Morin, P., and Dreux, M. (1995). Separation of transition metal cations by capillary electrophoresis, optimization of complexing agent concentrations (lactic acid and 18-crown-6).. Chromatogr. A 717, 393—408. 

As described above, titanium forms a stable complex with not only citric acid, but also lactic acid. Lactate ion does not form precipitate with strontium or barium. Therefore all of the titanium, barium, and strontium ions can be kept in an aqueous solution with use of lactic acid, that is, synthesis of Ba Srj. TiOj is possible. The ratio of the metallic elements can be arbitrarily changed, and thus all compositions of Ba Sri Ti03 can be synthesized. 

The electrochemical reduction of COj in aqueous solution on a functional dual-film electrode consisting of Prussian blue and polyaniline doped with a metal complex using a solar cell as the energy source led to the formation of lactic acid, formic acid, methanol, etc., and the maximum current efficiency for the COj reduction was more than 20 % at -0.8 V vs Ag I AgCI. 

From these results, it is considered that the electrophilic carbon atom of CO is bound to the amino group of PAn and the basic oxygen atom coordinates to the central metal of the complex. Such bifunctional activation of the substrate may lead to the reduction at the electrode potential close to the thermodynamic one. Lactic acid is probably generated through the formation of formaldehyde, the insertion of CO to the C-H bonds to form C-C-C bond and the reduction by... 

Lothenbach B, Furrer G, Schulin R (1997) Immobilization of heavy metals by polynuclear aluminum and montmorillonite compounds. Environ Sci Technol 31 1452-1462 Marklund E, Ohman L-O (1990) Equilibrium and structural studies of silicon(IV) and aluminum(III) in aqueous solution. 24 A potentiometric and Al NMR study of polynuclear aluminum(III) hydroxo complexes with lactic acid. Acta Chem Scand 44 228-234 Matzapetakis M, Raptopoulou CP, Terzis A, Lakatos A, Kiss T, Salifoglou A (1999) Synthesis, structural characterization, and solution behavior of the first mononuclear, aqueous aluminum citrate complex. Inorg Chem 38 618-619... 

Complexes of lactic acid with a wide variety of metal ions are known and their stability constants have been determined. A variety of techniques has been used in the study of the species formed in the solutions of this hydroxy acid and inorganic ions. Electrochemical and spectrophoto-metric methods have been used with the main aim of determining stability constants of the complex ions. CD and optical rotatory dispersion (ORD) have also proved to be powerful methods in studying, for instance, Mo, Mo , Cu" and Co", as well as lanthanide complexes. Very recently, Brittain et used circularly polarized luminescence (CPL) techniques in the study... 

Aliquat 336 is a commercially available extractant, extensively applied as a carrier in PlMs, which also has plasticizing properties. For this reason, it is frequently used in the manufacturing of PlMs without the addition of a separate plasticizer [17,18], Aliquat 336-based PlMs have been applied to the extraction and/or transport of anionic complexes of mainly heavy metals (e.g., As(V), Au(lll), Cd(ll), Co(ll), Cr(Vl), Cu(ll), Ni(ll), Pd(ll), Pt(lV), Re(Vll)), common anions (e.g., 1 , SCN ), and organic compounds (e.g., small saccharides, amino acids, lactic acid, thiourea) [2,3], Moreover, it has been recently employed in a PVC-based template for the preparation of Au nanoparticles (AuNPs). The nanoparticles were formed either in the bulk of the PIM or as a layer on the PIM surface by loading the membrane with AuClJ by anion-exchange, followed by in situ reduction with BH4 [19,20] or EDTA [21]. Capriquat is another liquid anion-exchanger similar in composition to Aliquat 336 with the major component being trioctylmethylammonium (TOMA) chloride [22]. 

Serrano and co-workers have investigated similar diketonato metal complexes bearing ten chiral aliphatic chains for potential uses as new types of ferroelectric discotic materials. The materials were obtained by replacement of the alkoxy chains of (55) by chiral chains derived from L-(—)-lactic acid (—20CC H(Me)OC H2 +i). Six, new, ten-chain metal complexes were prepared ((55) M = Cu, Pd, VO R = H, n = 6 and 7) and characterized fully. The NMR spectra... 

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