Preparation and biocidal properties of mixed butyl/cyclohexyl trialkyltin carboxylates

Two series of trialkyltin carboxylates containing butyl and cyclohexyl groups on tin, Bu_nCy_3-nSnO₂CR (n = 1, 2; R = n-Pr, Ph, 4-CIC₆H₄, 4-NO₂C₆H₄) have been synthesized and their structures characterized by IR, and ¹¹⁹Sn and ¹³C NMR spectroscopies. The compounds are five-coordinate, carboxylate-bridged polymers when R = n-Pr, while the other aromatic carboxylates are four coordinate. The compounds were also tested for their fungicidal, insecticidal and acaricidal activities.     

Photochemical properties of mixed-ligand complexes europium carboxylates

The photochemical behavior of mixed-ligand complexes of europium carboxylates with nitrogen-and phosphorus-containing neutral ligands of island and dimer types, Eu(L)₃ · xD · nH₂O and [Eu(L)₃ · xD]₂ · nH₂O (L is the trifluoroacetate, toluate, or cinnamate anion), was studied. During UV irradiation of the complexes of europium carboxylates with 1,10-phenanthroline and 2,2′-dipyridyl, a luminescence buildup was observed. EPR measurements demonstrated that the observed buildup of luminescence from europium occurs in parallel with the increase of the concentration of radical anions formed from neutral ligands.     

Synthesis,structures and properties of ternary rare earth complexes with fluorobenzoic acid and 1,10-phenanthroline

Three dimeric rare-earth complexes [Eu(p-FBA)₃(phen)(H₂O)]₂ (1), [Tb(p-FBA)₃phen]₂ (2), and [Tb(o-FBA)₃phen]₂ (3) (where p-FBA = p-fluorobenzoate, o-FBA = o-fluorobenzoate, phen = 1,10-phenanthroline) were synthesized and structurally characterized. All are neutral dimeric molecules. Complex 1 crystallizes in triclinic system, space group P 1. Each Eu(III) ion is eight-coordinate with one 1,10-phenanthroline, one monodentate carboxylate, one water and four bridging carboxylates. Complex 2 crystallizes in triclinic system, space group P 1. Each Tb(III) is also eight-coordinate with one 1,10-phenanthroline molecule, one bidentate chelating carboxylate and four bridging carboxylates. Complex 3 crystallizes in the monoclinic system, space group P2₁/c and consists of two crystallographically different binuclear molecules. Tb(III) ions are eight-coordinate with one 1,10-phenanthroline, one bidentate chelating carboxylate and four bridging carboxylates in both of them. Complex 1 shows bright red luminescence, 2 and 3 show green luminescence under UV light at room temperature. Thermal analysis indicates that are all quite stable to heat.     

Enthalpies and heat capacities of dissolution of some sodium carboxylates in water and hydrophobic hydration

Integral heats of solution ΔH_s of sodium carboxylates, C_nH_2n+1COONa (n=0, 1, 2, 3, 4, 5, and 7) and C₆H₅(CH₂)_nCOONa (n=0, 1, 2, and 3), in water at 25 and 35°C have been determined at very low concentrations. The heat capacities of dissolution at infinite dilution, ?C _p ^o , of sodium carboxylates have been derived by the integral heat method. The-CH₂-increment of ?C _p ^o in aliphatic carboxylates has been found to be 14 cal-deg^?1-mole^?1, which is close to the value derived from other series of compounds, indicating that the interaction of nonpolar moieties with water is independent of the hydrophilic group attached to it. On the other hand, the-CH₂-increment for the aromatic sodium carboxylates is much less (about 6 cal-deg^?1-mole^?1) than for the aliphatic sodium carboxylates, indicating that the hydrophobic interaction is affected by the aromatic end group.     

Structures and relationship between the 119SnNMR chemical shifts and pKa of their parent acids in organotin (I∇) carboxylates

Ten di-n-butyltin(I∇) carboxylates [(ⁿBu₂Sn-OCOR′)₂O]₂ and ⁿBu₂Sn(OCOR′)₂ (R′ = CCl₃, CHCl₂, CH₂Cl, PhCH = CH, and 2,2,3,3-tetramethylcyclopropyl) were synthesized and characterized by IR, ¹H, ¹³C, ¹¹⁹Sn NMR spectroscopy and elemental analysis. Together with other series of organotin(I∇) carboxylates, their structural features were discussed. The relationship between the ¹¹⁹Sn NMR chemical shifts in the organotin(I∇) carboxylates [(ⁿBu₂SnOCOR′)₂O]₂, ⁿBu₂Sn(OCOR′)₂, ⁿBu₃SnOCOR′, Ph₃SnOCOR′ and the pK_a values of their parent acids R′COOH was studied. The results have shown that the log[-δ(¹¹⁹Sn)] of the same series of carboxylates is linearly related to the pK_a of R′COOH. It seems that the better is the linearity between the log[−δ(¹¹⁹Sn)] and the pK_a, the more analogous are the structures of the same series of carboxylates. © 1996 John Wiley & Sons, Inc.     

Carboxylato-bis-dibenzoylmethanates of europium(III): Luminescence and magnetic properties

The luminescent and magnetic properties of europium(III) carboxylates, determined from the structure of Stark and Zeeman sublevels, are studied. It is found that the values of the λ_lum energy gap between the ground state ⁷ F ₀ and ⁷ F ₁ term in the luminescence spectra and λ_magn obtained from magnetochemical measurements correlate well.     

Preparation of Complexes of Nickel(II) Aryl Carboxylates with Morpholine and Piperidine

Complexes of nickel(II) aryl carboxylates with a general formula Ni(RC₆H₄COO)₂L₂ where R=H, p-CH₃. p-Cl, m- & p-NO₂; and L = morpholine and piperidine; have been prepared by the interaction of nickel(II) aryl carboxylates with a large excess of appropriate amine. Unlike parent anhydrous nickel(II) aryl carboxylates all these complexes are soluble in common organic solvents.     

Synthesis,structures and magnetic properties of a series of polynuclear copper(II)‐lanthanide( III) complexes assembled with carboxylate and hydroxide ligands

Heterometallic copper(II)‐lanthanide(III) complexes have been made with a variety of exclusively O‐donor ligands including betaines (zwitterionic carboxylates) and chloroacetate, which are dinuclear CuLn, tetranuclear Cu₂Ln₂, pentanuclear C_u3Ln₂, and octadecanuclear C_u12 complexes. The results show that subtle changes in both the carboxylates and acidity of the reaction solution can cause drastic changes in the structures of the products. Magnetic studies exhibit that shielding of the Ln³⁺ 4f electrons by the outer shell electrons is very effective to preclude significant coupling interaction between the Ln³⁺ 4f electrons and Cu²⁺ 3d electrons in either a mono‐atomic hydroxide‐bridged, or a carboxylate‐bridged system.     

Transport and co-transport of carboxylate ions and alcohols in cation exchange membranes

Understanding multi-component transport behavior through hydrated dense membranes is of interest for numerous applications. For the particular case of photoelectrochemical CO₂ reduction cells (PEC-CRC), it is important to understand the multi-component transport behavior of CO₂ electrochemical reduction products including mobile carboxylates (formate and acetate) and alcohols (methanol and ethanol) in the ion exchange membranes as one role of the membrane in these devices is to minimize the permeation of these CO₂ reduction products to the anolyte as they often oxidize back to CO₂. Cation exchange membranes (CEM) are promising candidates for such devices as they act to minimize the permeation of mobile anions, such as carboxylates. However, the design of new CEMs is necessary as the permeation of carboxylates often increases in co-permeation with alcohols. Here, we investigate the transport behavior of carboxylates and alcohols in two types of CEMs (1) a crosslinked CEM was prepared by free-radical copolymerization of a sulfonated monomer (AMPS) with a crosslinker (PEGDA), and (2) Nafion® 117. We observe an increase in both PEGDA-AMPS and Nafion® 117 diffusivities to carboxylates in co-diffusion with alcohols. We attribute this behavior to charge screening by co-diffusing alcohol that reduces the electrostatic repulsion between bound sulfonates and mobile carboxylates.     

A practical access to new pyrrolizine carboxylates via KHMDS-catalyzed carbocyclizations

Easy and effective preparation of new 1H-pyrrolizine carboxylates was achieved with high efficiency via KHMDS-induced carbocyclization of N-alkynyl proline carboxylates under substantially mild conditions. Meanwhile, some trans-diiodoallylic N-proline carboxylates were obtained from N-propargyl proline carboxylates using molecular I₂ with or without KHMDS. This method is quite feasible in terms of practical and quick access to the pyrrolizines and their derivatives over the formation of carbanions.     

The Solid-state Structures of a Non-hydrated Yttrium Carboxylate and a Yttrium Carboxylate Hemihydrate Obtained by Reaction of Yttrium Alkoxides with Carboxylic Acids

The yttrium carboxylates Y(methacrylate)₃ and Y(acetate)₃·0.5 H₂O were prepared by reaction of Y(OCH₂CH₂OMe)₃ with methacrylic or acetic acid and characterized by X-ray structure analyses. Both carboxylates have chain structures with both bridging and chelating-bridging carboxylate ligands. In Y(acetate)₃·0.5 H₂O, every second yttrium atom is nine-coordinate due to the additional coordination of a water molecule.     

Allenyl ester precursors for 1H-inden-1-ol carboxylates: comparisons with their propargylic equivalents having terminal alkyne functions

The reactivity of allenyl carboxylates, Ar(R¹)CCCH(O₂CR²) and their isomeric equivalents the terminal propargylic carboxylates, ArC(R¹)(O₂CR²)CCH, in gold-catalyzed carbocyclization to indenes provides information on 1,3 and 1,2-carboxylate shifts associated with their interconversion. Allenyl carboxylates transform specifically to 1H-inden-1-yl carboxylates in high yields, under Au^I-catalysis. Their equivalent propargylic carboxylates give complex mixtures of indene isomers and elimination products. Mechanistic tests indicate that interconversion of the terminal propargylic carbonate to its allene is at best slow in this case.     

The Solid-state Structures of a Non-hydrated Yttrium Carboxylate and a Yttrium Carboxylate Hemihydrate Obtained by Reaction of Yttrium Alkoxides with Carboxylic Acids

Summary. The yttrium carboxylates Y(methacrylate)₃ and Y(acetate)₃·0.5 H₂O were prepared by reaction of Y(OCH₂CH₂OMe)₃ with methacrylic or acetic acid and characterized by X-ray structure analyses. Both carboxylates have chain structures with both bridging and chelating-bridging carboxylate ligands. In Y(acetate)₃·0.5 H₂O, every second yttrium atom is nine-coordinate due to the additional coordination of a water molecule.     

The effect of carboxylate anions on the formation of clathrate hydrates of tetrabutylammcnium carboxylates

The solid-liquid phase diagrams of binary mixtures of water with tetrabutylammonium carboxylate having an unsaturated alkyl group in the carboxylate anion ((n-C₄H₉)₄NOOCR; R=C₂H₃–C₉H₁₇) were examined in order to confirm the formation of clathrate-like hydrates. The results are summarized as follows: (1) the formation of a clathrate-like hydrate is newly confirmed for all the 13 carboxylates examined; (2) these hydrates are classified into three groups I, II, and III on the basis of the hydration numbers; (3) the group I hydrates, which are formed by the carboxylates with R=C₂ and R=C₃, have hydration numbers around 30 and are the most stable hydrates among those examined in this study; (4) the group II hydrates, with hydration numbers around 39, are formed by all the carboxylates with R=C₄ and C₅ including sorbate and are less stable than the group I hydrates; (5) the group III hydrates, with hydration numbers around 30 like the group I hydrates, are formed by carboxylates with long alkyl chains such as 2-octenoate and 2-decenoate and are generally unstable.     

Structures of molecular complexes of SbCl5 with pyridine and acetonitrile: equal bond lengths,different stability

Molecular structure of crystalline complex SbCl₅ ? Py was determined for the first time and the structure of the complex SbCl₅ ? AN was refined by means of single crystal X-ray diffraction analysis. It is shown that donor-acceptor Sb–N bond lengths for these complexes are equal within the experimental error. Quantum chemical calculations of the complexes in the gas phase reveal that the energies of the donor-acceptor bond Sb–N are 88 and 180 kJ mol^?1 for SbCl₅ ? AN and SbCl₅ ? Py, respectively. It is established that the length of the donor-acceptor bond Sb–N in the crystal cannot serve as a measure of its strength.

     

Copolymeric nano/microgels of N-isopropylacrylamide and carboxyalkyl methacrylamides: Effect of methylene chains and the ionization state of the weak acids on size and sensitivity to pH and temperature

ABSTRACT

We prepared nano/microgels by precipitation copolymerization of N-isopropylacrylamide (NIPAAm), and one of three different carboxyalkyl methacrylamides [methacryloylamido hexanoic acid (M₅), 8-methacryloylamido octanoic acid (M₇), and 11-methacryloylamido undecanoic acid (M₁₀)], either in the acid forms or as carboxylates (potassium salts). The hydrodynamic diameter (Dh) of the nano/microgels prepared with the carboxylates was smaller (≈100 nm for M₁₀ copolymers), compared to the size of homopolymeric NIPAAm microgels prepared by dispersion polymerization (around 600 nm), indicating that the carboxylates act as surfactants reducing the size of the seeds during the polymerization process. These materials presented a swollen-shrunken transition temperature (T _tr) similar to the T _tr of the homopolymeric NIPAAm microgels, without pH sensitivity. On the other hand, the copolymeric microgels prepared from the acid form of the comonomers have a similar or bigger size than NIPAAm microgels. For these copolymers, the T _tr can be tuned by the type and proportion of acid comonomer used and present pH sensitivity. This is important for biomedical applications such as positive temperature control release. Polyelectrolyte titration demonstrates that the nano/microgels prepared with the carboxylates behave as hard spheres, while the microgels prepared with the weak acid behave as porous materials.     

Diorganotin(IV) and triorganotin(IV) derivatives of diphenic acid

The diorganotin(IV) and triorganotin(IV) derivatives R₂SnA (R = Me, n-Pr, n-Bu, n-Oct) and (R₃Sn)₂A [R = Me, Ph, cyclohexyl (Cyh); A = an anion of diphenic acid] have been prepared and characterized by elemental analysis, IR, ¹H and ¹³C NMR spectroscopies. Tetrahedral tin forms a part of a diphenate cyclic ring in the diorganotin complexes with unidentate carboxylates, which have further been used for the synthesis of cyclic acid anhydrides. The soluble dinuclear triorganotin complexes (Me, Ph) possess symmetrically bonded carboxylates while the less soluble compound (Cyh₃Sn)₂A has two asymmetrically bonded carboxylates. All have a trigonal bipyramidal structure with R₃Sn units remote from each other.     

Characterization of the first mixed-valent liquid-crystalline materials. Synthesis and structural properties of new binuclear ruthenium carboxylates

Abstract

The syntheses and structural properties of new binuclear ruthenium (II, III) complexes with long chain carboxylates, of general formula Ru₂(RCO₂)₄X (R = C₈H₁₇, C₁₁H₂₃ and X = C1, RCOO), are reported. The thermodynamic behaviour of these compounds is strongly influenced by the nature of the counterion X. The chloro complexes (X = CI) are not mesomorphic whereas the carboxylato species (X = RCOO) are shown to exhibit a thermotropic columnar mesophase, thus providing the first example of a mixed-valent liquid-crystalline material.     

Solid-phase mechanochemical synthesis of zirconium tetracarboxylates

The solid-phase synthesis of zirconium carboxylates Zr(OOCR)₄ (R = Alk) by reactions of zirconium tetrachloride with metal carboxylates (isobutyrate, pivalate, and palmitate) (the molar ratio ZrCl₄: RCOOM is 1: (4–5)) under mechanical activation is developed. Further thermal treatment of the reaction mixture and extraction with an organic solvent afford zirconium carboxylates.     

Fluorescence properties of mixed-ligand europium carboxylates

Mixed-ligand binuclear and mononuclear europium carboxylate complexes with nitrogen-and phosphorus-containing neutral ligands have been studied by luminescence and X-ray photoelectron spectroscopy. The coordination of neutral ligands through the nitrogen donor atom leads to an increase in electron density at the Eu³⁺ atom. In groups of carboxylates of the same type, the coordination of neutral donor ligands leads to an increase in the relative intensity of the ⁵ D ₀-⁷ F ₄ electric dipole transition. Analysis of the luminescence excitation spectra points to the presence of two excitation energy transfer channels for mixed-ligand europium trifluoroacetate and toluate complexes and of one channel for europium cinnamate complexes with neutral ligands.