Mixed Carboxylate Research Articles

Synthesis and luminescent properties of the first series of lanthanide complexes based on sebacate and 2,5-pyridinedicarboxylate

Abstract By using 2,5-pyridinedicarboxylate and sebacate as rigid and flexible mixed carboxylate linkers, five new 3D lanthanide complexes, [Ln(seb) 0.5 (2,5-pydc)(H 2 O)] (Ln = Eu ( 1 ), Nd ( 2 ), Sm ( 3 ), Pr ( 4 ) and Tb ( 5 ), H 2 pydc = 2,5-pyridinedicarboxylic acid, H 2 seb = sebacate acid) with macroporous structures, have been synthesized. Complexes 1–5 were characterized by elemental analysis, ICP spectrometer and IR spectroscopy. In particular, the structures of 1–3 were further determined by single-crystal X-ray diffraction. Structural analyses reveal that complexes 1–3 have intricate 3D frameworks, which are constructed by 2,5-pyridinedicarboxylate and sebacate ligands. In addition, the thermogravimetric analysis of 1–3 and photoluminescent properties of 1 and 5 are also discussed in detail.

Polymeric Frameworks Constructed from Bulky Carboxylates and 4,4′-Bipyridine Linkages: Synthesis, Crystal Structures, and Properties

Six novel coordination polymers, {[M2(L1)2(μ2-L1)2(4,4′-bipy)2]·CH3OH}n (HL1 = 3-(4-carboxylphenylamino)-1-ferrocenyl-2-butylen-1-one, 4,4′-bipy = 4,4′-bipyridine) (M = Zn (1) or Cd (2)), {[Cd2(η2-L2)2(μ2-η2-L2)2(4,4′-bipy)2]·CH3OH}n (HL2 = N-phenylanthranilic acid) (3), {[Cd2(μ-L3)(μ2-L3)(η2-L3)(4,4′-bipy)2(H2O)2]·NO3}n (HL3 = cinnamic acid) (4), {[Cd2(μ2-L4)4(4,4′-bipy)2]·2H2O}n (HL4 = hippuric acid) (5), and {[Cd2(μ2-η2-L5-η2)2(SO4)(4,4′-bipy)2(H2O)2]·5H2O}n (HL5 = 1-(carboxymethyl)-1,3-benzimidazol-3-ium-3-acetate) (6), have been synthesized and structurally characterized by single-crystal X-ray diffraction method. Polymers 1−4 exhibit one-dimensional (1-D) ladder-like structures, in which carboxylate ligands bridge two metal ions forming dinuclear cores, and 4,4′-bipy ligands link these cores. In polymers 5 and 6, the carboxylate-linked chains [Cd2(μ2-L4)4]n or mixed carboxylate and SO42− linked [Cd2(μ2-η2-L5-η2)2(SO4)]n chains are bridged by 4,4′-bipy ligands to form two-dimensional (2-D) sheet stru...

A mixed carboxylate polymer as an intermediate during synthesis of mononuclear bis -3, 5-dimethylpyrazole copper(II) benzoates

The crystal structures of bis-3,5-dimethylpyrazole copper(II) 4-methylbenzoate, bis-3,5-dimethylpyrazole copper(II) 3-methylbenzoate, bis-3,5-dimethylpyrazole copper(II) 4-nitrobenzoate show that 3,5-dimethylpyrazole in the cis or trans positions is related to axial distortion of Cu-O bond in carboxylate groups. A metastable mixed carboxylate co-ordination polymer presumably intermediate to the one described above which has alternate paddlewheel and mononuclear units is structurally characterized.

Unprecedented 7-connected 3 6 · 4 13 · 6 2 structural topology: Praseodymium-based coordination polymers built from mixed carboxylate ligands

A new lanthanide coordination polymer [Pr(dpdc)(nta)] n ( 1) (H 2dpdc = 2,2′-diphenyldicarboxylate acid, Hnta = nicotinic acid) has been prepared and characterized by IR, element analysis, TGA, and single-crystal X-ray diffraction. 1 is built up from two different carboxylate ligands and shows an unusual two-dimensional (2D) 7-connected 3 6 · 4 13 · 6 2 topological network. The zero-field splitting parameter was obtained by varied magnetic susceptibilities measurement (2–300 K).

Unusual silver coordination by mono-carboxylate utilization of a poly-carboxylate anion, solid-state structures of silver-tetrachlorophthalate with phthalazine and amine ligands

Silver carboxylate coordination with the tetrachlorophthalate anion, in combination with neutral donor ligands, has been found to deviate from other known poly-carboxylate complexes. Both complexes reported here, bis-[tetrachlorophthalato-silver phthalazine] and bis-[ammino-tetrachlorophthato-silver di-ammino-silver], utilize mixed carboxylate bonding types for silver coordination. In the case of the phthalazine ligand, both chelating and monodentate carboxylates form the framework for the oligomeric structure. In the case of the ammine ligand, one carboxylate forms a monodentate connection to a silver-ammine group, while the other is simply involved with hydrogen bonding to lock in a [(Ag–NH 3) 2–Ag–NH 3] substructure with an adjacent tetrachlorophthalato-silver unit. Both structures exhibit supramolecular connections via hydrogen bonding and π–π interactions.

A new one-dimensional Mn(ii) complex containing two enantiomeric subunits with mixed carboxylate, pyridine and sulfinate bridges

The first O,O'-bonded metal-stabilized sulfinate has been isolated and structurally characterized to show a novel one-dimensional chain structure containing both the enantiomers of the subunit Mn(2-sinic)(DMSO)2.

Mixed Carboxylate-Bridged Dimanganese(II/III) Compounds Prepared by an O2-Dependent Oxidative Cleavage of Ketones

The structure of an O(2)-sensitive Mn(II)-Mn(II) complex with an unsymmetrical perchlorate bridge is reported. This complex promotes an O(2)-dependent oxidative cleavage of ketones giving mixed carboxylate complexes.

A chiral mixed carboxylate, [Nd 4(H 2O) 2(OOC(CH 2) 3COO) 4(C 2O 4) 2], exhibiting NLO properties

Reaction of a mixture of neodymium carbonate, HCl, oxamic acid and glutaric acid under hydrothermal conditions gives rise to a new mixed carboxylate of neodymium, [Nd 4(H 2O) 2(OOC(CH 2) 3COO) 4(C 2O 4) 2], I. The structure, determined using single crystal X-ray diffraction, comprises a helical column formed by the grafting of the oxalate unit on to helical NdO 9 chains, cross-linked by the glutarate anions. It is noteworthy that the pitch of the helix is equivalent to the length of the oxalate unit. Furthermore, I shows about 1.1 times the SHG activity of urea.

Cadmium(II)bis(oxalato)cobaltate(II)- pentahydrate

A mixed metal carboxylate, cadmium(II)bis(oxalato)cobaltate(II)pentahydrate, has been synthesized and characterized by elemental analysis, IR spectral, reflectance and X-ray powder diffraction studies. Thermal decomposition studies (TG, DTG and DTA) in air showed that the compound decomposed to CdCoO3 at 370°C through the formation of an anhydrous compound at ~194°C. Finally, CdCoO2 is generated at 1000°C. DSC study in nitrogen up to 550°C showed the formation of a mixture of CdO and Co3O4 as end products. The kinetic parameters have been evaluated for the dehydration and decomposition steps using four non-mechanistic equations, i.e., Freeman and Carroll, Coats and Redfern, Flynn and Wall, MacCallum and Tanner equations. Using seven mechanistic equations, the rate controlling processes of the dehydration and decomposition mechanism are also inferred. The kinetic parameters, DH and DS obtained from DSC are discussed. IR and X-ray powder diffraction studies identified some of the decomposition products. A tentative mechanism for the decomposition in air is proposed.

Synthesis, structure and fluorescence of a novel three-dimensional inorganic–organic hybrid polymer constructed from trimetallic clusters and mixed carboxylate ligands

A new inorganic–organic hybrid framework coordination polymer, Cd 3(BDC) 0.5(BTC) 2(DMF)(H 2O)·3DMF·H 3O·H 2O 1, in which two carboxylate ligands, 1,4-benzenedicarboxylic acid (H 2BDC) and 1,3,5-benzenetricarboxylic acid (H 3BTC), coordinate with cadmium ions, has been synthesized under mild conditions and its structure solved by single-crystal X-ray diffraction (XRD) analysis. Polymer 1 crystallizes in the monoclinic system, space group P2 1/ c (No. 14) with a=15.750(3) Å, b=14.501(3) Å, c=19.363(4) Å, β=113.67(3)°, V=4050.4(14) Å 3, Z=4, R1=0.0374 and w R2=0.1148. Its structure revealed that the nine vertices of the secondary building units are linked by benzene rings from both H 3BTC and H 2BDC ligands to form a 3D network with 10×10 Å channels along [001] direction. Complex 1 is characterized by inductively coupled plasma analysis, powder XRD, infrared spectroscopy and thermogravimetric analysis. Polymer 1 exhibits intense fluorescence at 358 and 377 nm with λ excitation=208 nm in the solid state at room temperature.

Intramolecular versus Intermolecular Hydrogen Bonding of Coordinated Acetate to Organic Acids: A Neutron, X-ray, and Database Study

The effect of strong intra- and intermolecular hydrogen bonding on molecular geometry in carboxylate coordination complexes is examined by means of a search of the Cambridge Crystallographic Database. Accurate hydrogen-bonding parameters for two representative examples, [Cu2(μ-O2CCH3)4(CH3CO2H)2] (1; intramolecular) and [Cu2(μ-O2CCH3)4(H2O)2]·2CH3CO2H (2; intermolecular), are determined by single-crystal neutron diffraction. Electronic effects are probed by the synthesis and characterization of a further mixed carboxylate derivative, [Cu2(μ-O2CCH3)2(μ-O2CCF3)2 (H2O)2]·2CH3CO2H (5).

Synthesis and properties of nickel borate acylate as a new rubber-steel cord adhesion promoter

The synthetic method of nickel borate acylate (NBA), a kind of rubber-steel cord adhesion promoter (AP), through nickel carbonate, borate and mixed carboxylic acid was studied. The preparation of nickel carbonate could be performed through reaction of nickel sulfate with sodium carbonate in aqueous solution, in which fractional conversion of nickel was more than 99.9%. The mixed nickel carboxylate was prepared by the reaction of nickel carbonate with isooctanoic acid and acetic acid, under strong stirring for 2 h, the mole ratio of these chemicals were 1:1:1.1 respectively, and water should be removed completely by adding of inert organic solvent after reaction was finished so as to avoid hydrolysis of tributyl borate in the second reaction. NBA was synthesized by reaction of mixed nickel carboxylate with tributyl borate under strong stirring at 200–250 °C for 6 h. By detection and comparison with 680C product from Manobond Company of England, the NBA synthesized through isooctanoic acid and tributyl borate was very similar to product 680C in IR data, 300% fixed extension strength, tensile strength, hardness and cure curve, and was slightly lower than those of product 680C in tensile failure extensibility and hot air aging. The experimental results show that the prepared NBA can be used as rubber-steel cord AP.

An experimental study on alkaline/surfactant/polymer flooding systems using nature mixed carboxylate

The orthogonal-test-design method was used to determine the optimal formula by phase behavior and transient interfacial tension (IFT) studies, respectively. The results indicate the major components are cheap, naturally mixed carboxylate SDC (0.5%), alkaline NaHCO 3/Na 2CO 3 weight ratio of 1 (1.0%), and HAPM (1000 mg dm −3). In the coreflood experiment, their oil recovery will be increased by a factor of 25.2 and 26.8% the original oil in place (OOIP).

Electrophilic substitution of (diamine)tetrahydroxoplatinum(IV) with carboxylic anhydrides. Synthesis and characterization of (diamine)platinum(IV) complexes of mixed carboxylates.

A novel series of (diamine)platinum(IV) complexes of mixed carboxylates have been synthesized by electrophilic substitution of the tetrahydroxoplatinum(IV) complex (dach)Pt(OH)4 (dach = trans-(+/-)-1,2-diaminocyclohexane) with three different carboxylic anhydrides, pivalic, acetic, and trifluoroacetic anhydrides. Consecutive two-step acylations with two different carboxylic anhydrides in acetone or dichloromethane gave the mixed carboxylate complexes (dach)Pt(O2CR)x(O2CR')4 - x (R = C(CH3)3 or CF3, R' = CH3, x = 1-4) including all the possible stereoisomers, which could be separated and identified by means of HPLC, column chromatography, 1H NMR, and X-ray crystallography. From analysis of the reaction products we have found that the positions of electrophilic substitution of (dach)Pt(OH)4 were influenced by the kinds of carboxylic anhydrides exhibiting different electrophilicity or steric effects. The initial substitution by the first reactant occurs more favorably on axial OH, but in the case of pivalic anhydride, equatorial substitution is favored probably because of the bulkiness of the pivalate group. Such a result seems to be related to their stereochemical factors rather than to differences in electrophilicity. The lipophilicity of the title complexes was affected not only by the carbon numbers of substituents but also by the conformation of the resulting compound.

What is the Criterion for Selecting Alkaline/Surfactaint/Polymer Flooding Formulation: Phase Behavior or Interfacial Tension

An experimental study on determination of alkaline, surfactant, polymer (ASP) flooding systems using natural mixed carboxylate was conducted to examine the decisive factor for ASP flooding, phase behavior or interfacial tension. The volume and color of middle phase liquid were observed, the transient interfacial tension at different salt and alkaline concentrations were measured and, finally, coreflood test in laboratory were made. The results showed the flooding system with larger volume and brown color of middle phase emulsion sometimes not to obtain better oil recovery efficiency. The primary and more important phenomenon affecting the oil recovery is a lower or ultralow minimum interfacial tension value at the crude oil/soluble phase interface.

Surface analysis of poor printability PVC films

Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to analyze the surfaces of PVC films with poor printability. FTIR indicated that, independent of formulation, the migrating species were metal carboxylates. Different techniques penetrate the surface to different depths allowing examination of a range of surface layers. XPS indicated that, in the worst case, the upper surface layer was comprised almost exclusively of a mixed metal carboxylate. Atom percentages obtained by XPS indicated hydrolysis of the mixed metal carboxylate at the vinyl surface.

Low-temperature formation of alpha alumina powders from carboxylate and mixed carboxylate precursors

Formation of alpha alumina fine powders from aluminum carboxylate and mixed carboxylate precursors have been studied using thermoanalytical and powder X-ray diffraction techniques. Among these carboxylates, aluminum acetate and formoacetate produce alpha alumina below 1000°C, whereas, the other precursors require about 1200°C. The nature of the precursor has been found to influence the course of thermal decomposition and the sequence of phase evolution. The resultant alpha alumina powders have been have been characterised employing surface area and porosity measurements.

Cleavage Oftin-Aryl Bond(S) by Monohalocarboxylic Acids: The Steric Factor Role

All four tin-carbon bonds of tetra-p-tolyltin can be successively cleaved by iodoacetic acid. Reactions with tetra-m-tolyltin are sluggish and only one tin-carbon bond is cleaved, even in the presence of an excess of the acid. Tetra-o-tolyltin does not react under similar conditions. Stene factors arc thought to be responsible for this difference in reactivity of tetratolyltins. The monocarboxylates were not isolated in case of Ph4Sn (except with CCl3COOH). Tetraphenylgermanium gives only the monocarboxylates Ph3GeOOCR', (R = CH2CI, CH2Br, CH2I), but all the Ph-Pb bonds in tetraphenyllead may be successively cleaved. Tri-p-tolyltin chloride reacts with iodoacetic acid to give a mixed chloro halocarboxylate, (p-MeC6H4)2SnC1(OOCCH2I), but attempts to prepare a mixed carboxylate by reacting (p-MeC6H4)3SnOOCCH2CI with HOOCCH2I failed.

Camphoric acid derivatives as components of glass systems: the structure of 3-methyl (1 R,3 S)-(+)-camphorate

3-Methyl (1 R,3 S)-(+)-camphorate (III) has been found to have a wider potential as a component of mixed carboxylate glasses than does the parent acid, (1 R,3 S)-(+)-camphoric acid (I). The solution and solid-state structures of (III) have been determined by NMR ( 1H and 13C) and single crystal X-ray diffraction, respectively. Infrared spectral and optical rotation data are also presented. Each molecule is linked to two other molecules by strong intermolecular hydrogen bonds [O2⋯O3=2.716(Å)] to give chains of molecules. With care, zinc camphorate can be successfully incorporated into glass forming systems, but its scope is limited: the calcium and copper salts have no value as glass formers.

Polymeric and mixed carboxylate compounds: Crystal structures of [Zn(tiglate)2]x and [Zn2(tiglate)3(crotonate)

The crystal structures of [Zn(O2CC(CH3)CHCH3)2]x and [Zn2(O2CC(CH3)CHCH3)3-(O2CCHCHCH3)]x have been determined by single crystal X-ray diffraction. Both structures consist of chain polymers, in which pairs of zinc atoms are bridged alternately by three syn-syn carboxylates and by one syn-anti carboxylate. In the mixed carboxylate structure, the crotonate takes up preferentially the syn-anti bridge position. Vibrational and elemental analysis data indicate that the spontaneous solid-state reaction of zinc tiglate in air, accelerated for the tiglate and observable also for the mixed carboxylate compound by γ-ray or X-ray irradiation, gives an oxocentered tetranuclear complex [Zn4O(O2CR)6] rather than a polymerization through cross-linking of the unsaturated carboxylates.