Triethylammonium Ion Research Articles

Convenient Route to Alkylene Dithiophosphato Ligands: Synthesis and Crystallographic Analysis of [OCH2CMe2CH2OPS2HNEt3

Triethylammonium salts of O,O′-alkylene dithiophosphato like OGOPS2HNEt3, [where, G = –CH2CMe2CH2–(1), –CH2CEt2CH2–(2), –CMe2CH2CHMe–(3) and –CMe2CMe2–(4)] have been synthesized in quantitative yield by the direct reaction of P2S5 with 1,2- and 1,3-substituted glycols in presence of triethylamine, Et3N, in 1:2:2 molar stoichiometry in toluene. These have been mainly characterized by molecular weight, IR and NMR (1H, 13C and 31P) spectroscopic studies. Single crystal X-ray structure analysis of [OCH2CMe2CH2OPS2HNEt3] reveals that phosphorus atom is tetrahedrally bonded to two sulfur atoms and two oxygen atoms in the ring and the molecule exists as discrete cation and anion. The structure is stabilized by cation–anion N–H···S hydrogen bonded interactions. Antiparallel pattern of triethylammonium ion is sandwiched within the two-dimensional layers of the ring system. Crystallographic analysis of [OCH2CMe2CH2OPS2HNEt3] reveals that phosphorus atom is tetrahedrally bonded to two sulfur atoms and two oxygen atoms in the ring and the molecule exists as discrete cation and anion. The structure is stabilized by cation-anion N-H···S hydrogen bonded interactions. Antiparallel pattern of triethylammonium ion is sandwiched within the two-dimensional layers of the ring system.

Cross-Coupling of 5,11-Dibromotetracene Catalyzed by a Triethylammonium Ion Tagged Diphenylphosphine Palladium Complex in Ionic Liquids

Suzuki–Miyaura cross-coupling reactions of 5,11-dibromotetracene with arylboronic acids, using a triethylammonium-tagged palladium(II) diphenylphosphine complex as catalyst in a pyrrolidinium-based ionic liquid (IL), allowed the preparation of new 5,11-diaryl-substituted tetracenes in good to excellent yields. The synthesis of the new 5,11-diboronic-tetracene bis-pinacolate ester and its use in Suzuki–Miyaura cross-coupling reaction with aryl bromides in IL are also reported.

Nigericin-mediated liposome loading of topotecan: Is nigericin a potential drug release regulator?

Topotecan was loaded into large unilamellar vesicles using nigericin-generated pH gradient or with triethylammonium (TA) ion gradient. Despite that in both loading methods, the encapsulated counter ion was 5-sulfosalicylate (5ssa), the resultant formulations exhibited distinct properties. In NaCl-containing release buffer, vesicles prepared with nigericin/Na + system could release topotecan at a faster rate than 5ssa–TA vesicles, whereas in the absence of Na +, there was no difference in the drug release kinetics. In plasma, both formulations could prolong the circulation halftime of topotecan, but 5ssa–TA vesicles were more able to stabilize the encapsulated topotecan, as evidenced by the increased t 1/2 and decreased conversion of lactone to carboxylate form. However, the improved drug retention did not mean the elevated safety and efficacy. In L1210 ascitic tumor model, the administration of 5ssa–TA vesicles at 10 mg/kg induced the early death of ∼60% mice at 6–7 days. In contrast, the treatment with nigericin/Na + vesicles at the same dose level resulted in a mean survival time of ∼18.0 days, ∼1.38-fold of that of free topotecan. In addition, the formulation was safer than free topotecan. The results indicated that nigericin could be used as release regulator to optimize drug release kinetics, resulting in safe and efficacious liposome-based topotecan formulation. The results were promising since no liposome topotecan formulations with reduced toxicity were reported.

Mitochondria-targeting properties and photodynamic activities of porphyrin derivatives bearing cationic pendant

Four meso-tetraphenylporphyrin derivatives bearing either triphenylphosphonium ion-(P1 and P2) or triethylammonium ion-(P3 and P4) terminated alkoxy group at either para-(P1 and P3) or meta-(P2 and P4) position of one meso-phenyl group were designed and synthesized. P1-P4 show similar absorption and fluorescence emission spectra and (1)O(2) quantum yields. The more lipophilic nature of triphenylphosphonium ion over triethylammonium ion renders P1 and P2 higher octanol/water partition coefficients than P3 and P4. Confocal fluorescence microscopy proved that P1-P4 are all mitochondria-targeting. MTT assay showed that P1-P4 presented significant phototoxicity at the concentrations that dark toxicity is negligible towards human breast cancer cell line MCF-7 cells, displaying their application potential in PDT.

Effects of Organic Impurities on Chloralkali Membrane Electrolyzer Performance

Laboratory chloralkali membrane electrolyzer tests showed a dramatic voltage increase and mild catholyte foaming when low levels of chloromethyl triethylammonium chloride (CTACl), a quaternary ammonium salt, were present in the feed brine. Current efficiency was not measurably affected by CTACl. In contrast, laboratory membrane electrolyzers showed no voltage sensitivity to sodium gluconate, bisphenol A, or triethylamine, contaminants that are often present in interfacial polycarbonate plant byproduct brine. The voltage increase and onset of catholyte foaming were rapid when the feed was switched from ultrapure brine to CTACl-containing brine, requiring about 3 h to achieve a steady state. Both effects were completely reversible, but the system required about 20 h to return to baseline voltage after the feed was switched back to ultrapure brine. The cell voltage was remarkably sensitive to CTACl: 8 ppm CTACl yielded a 200 mV voltage increase vs ultrapure brine. Cyclic voltammetric measurements with CTACl-spiked brine showed no effect of CTACl on anode or cathode overpotentials. At steady state, 87% of the feed chloromethyl triethylammonium ion (CTA+) is recovered either in the electrolyzer catholyte as the hydroxide, CTAOH (56%), or in the depleted brine as CTACl (31%), which demonstrates that CTA+ is rather stable toward chloralkali conditions. It is concluded that the increased cell voltage is caused by chloromethyl triethylammonium ions adsorbing onto membrane ion exchange sites, which reduces the population of sites for sodium ion transport, and that catholyte foaming is caused by the presence of CTAOH in the catholyte. An adsorbent screening study showed that various carbons, including Ambersorb 572, are effective for CTACl removal from brine. A laboratory electrolyzer fed with Ambersorb 572 treated plant brine showed normal voltage and no catholyte foaming.

Effects of Cationic Species on Visual Color Formation in Model Maillard Reactions of Pentose Sugars and Amino Acids

Effects of cationic species on Maillard browning were examined after heating (ca. 100 degrees C) aqueous pH 7.2 buffered solutions of amino acids and pentose sugars. Metallic ions of Group I metals (Li, Na, K, Rb and Cs) produced a small increase in browning (A420), but somewhat greater effects were observed with ions of Group II metals Ca and Mg. Browning was suppressed by triethylammonium ion, but unaffected by a salt of the stronger base, guanidine. The quaternary amine salt choline chloride produced enhanced browning and served as a model for phospholipid involvement in Maillard reactions. With alpha,omega-diamino acids increases in browning were observed which related to lowered pK2 values resulting from positively charged omega-substituents in these molecules.

ESI-FTICR investigation of triethylammonium ion-driven resorcin[4]arene dimer formation and structure.

In the course of mass spectrometric measurements a self-assembled hydrogen bonded resorcinarene dimer was observed, the formation of which was driven by the binding of triethylammonium ion as a guest and as an ionic label.

A kinetic study of the permanganate oxidation of triethylamine. Catalysis by soluble colloids

AbstractThe kinetics of the reaction between permanganate ion and triethylamine in aqueous phosphate buffers (pH 6–8) has been studied. The reaction is autocatalytic, a soluble form of colloidal manganese dioxide temporarily stabilized in solution by adsorption of phosphate ions on its surface having been identified as the autocatalyst. The reaction is also catalyzed by gum arabic. Mechanisms in agreement with the kinetic data are proposed for the reaction pathways taking place in the bulk solution (for both triethylamine and triethylammonium ion as reductants) and on both the gum arabic and manganese dioxide colloidal particles.

Determination of ranitidine in plasma by high-performance liquid chromatography

A high-performance liquid chromatographic method has been developed for the determination of ranitidine in plasma. Ranitidine was extracted with acetonitrile by adding it to the plasma and then salting it out with potassium carbonate. The chromatographic column was 5-μm ODS silica, the mobile phase being acetonitrile-7 mM triethylammonium ion in phosphoric acid (pH 3.00) (30:70 v/v). The ranitidine peak was monitored at a wavelength of 315 nm, the retention time for ranitidine being 4.6 min. A limit of detection of 3 ng ml −1 was obtained for a 100-μl injection of ranitidine. The method was found to be reproducible with a relative standard deviation (RSD) between 0.8–5.3% ( n = 5) over the concentration range 25–80 ng ml −1 in plasma. The ranitidine concentration was determined in 18 different patients' plasmas. Ranitidine and its metabolites ranitidine S-oxide, ranitidine N-oxide and desmethylranitidine, were also studied for chromatographic resolution from each other. It was shown that a group of common drugs did not interfere with ranitidine determination.

Absolute configuration of Rp-uridine 3',5'-cyclic phosphorothioate.

Triethylammonium uridine-3',5'-cyclic phosphorothioate crystallizes in space group P2(1)2(1)2(1), a = 7.177(1), b = 13.155(6), c = 21.114(7) A, C15H26N3O7PS, MW 423.4, Z = 4, dx = 1.41g/cm3. The crystal structure was solved by direct methods on the basis of 1493 counter X-ray diffraction data (CuK alpha) and refined to R = 5.1%. The configuration of the thiophosphate group is Rp; conformational parameters are: glycosyl torsion angle anti, -151.9(5) degrees, sugar pucker C(3')-endo with P = 27.3 degrees, vmax = 45.5 degrees, six-membered cycle in chair form. The bond distances in the non-esterified P-S and P-O suggest that the negative charge is distributed between the groups. As illustrated in this and other studies, P-O has a much higher affinity for hydrogen bonds than P-S, indicated here by interactions with triethyl-ammonium N-H and O(2')-H as donors. One additional hydrogen bond N(3)-H---0(4) ties the bases which form a ribbon-like structure. 0(2) and S are not engaged in hydrogen bonds. The triethylammonium ion is two-fold disordered.

Infrared spectroscopic studies of hydrogen bonding in triethylammonium salts. Part 3.—Strong hydrogen bonding

Infrared absorption spectra of solutions of a number of strongly hydrogen-bonded triethyl-ammonium salts Et3N+H⋯A– have been obtained. Special attention has been paid to changes in the band parameters of the νN+H stretching mode. A comparison is made between Fermi resonance of internal modes of the triethylammonium ion and a new type of strong resonance coupling of internal modes in which the intermolecular bending mode of the hydrogen-bonded complex Et3N+H⋯A– participates. The zero, first and second moments of the νN+H stretching-mode bands have been measured. The inter-relation between these values has been checked over the permissible range of interionic hydrogen-bonding strengths in the ion pairs Et3N+H⋯A–. Hydrogen-bond energies of the triethylammonium salts studied have been estimated by a spectral method.

Specific interaction of the triethylammonium ion with substituted pyridines in nitrobenzene and inortho-Dichlorobenzene

The dissociation constants Kd of triethylammonium picrate have been determined from conductimetric measurements in nitrobenzene (NB) and in ortho-dichlorobenzene (ODCB) with and without pyridines being used as ligands. In the absence of any ligand, the enhancement of the dissociation in NB as compared with that in ODCB cannot be explained solely by the increase of the dielectric constant, but shows the existence of specific interactions of the former solvent with the ions. The results obtained in the presence of ligands are consistent with the formation of a 1:1 cation-pyridine hydrogen-bonded complex. The constantk 1 + for the formation of theis complex has been determined for six substituted pyridines in both solvents. Logk 1 + varies linearly with the Hammett parameter σH of the substituent. The slope ρ of the Hammett relation is −1.86 in NB and −2.90 in ODCB. The difference can be ascribed to specific interactions between NB and the pyridines which become stronger when the pyridine is more basic.

On the structure-activity relationships and mechanism of organotin induced, nonenergy dependent swelling of liver mitochondria

Organotin-induced, nonenergy dependent swelling of isolated rat liver mitochondria has been investigated. The organotins which were most active as swelling agents had three carbon-tin bonds, n-octanol: water partition coefficients greater than one, extracted chloride ions from water into benzene, and facilitated the diffusion of chloride ions through a benzene phase. Compounds having one, two, or four carbon-tin bonds exhibited low activity as swelling agents. Mitochondria were most sensitive to organotin-induced swelling when the major cation in the medium was the ammonium or triethylammonium ion; however, high concentrations of active organotins caused swelling which was independent of the nature of the medium. Bis-(triphenyltin)-sulfide exhibited low activity and sodium sulfide, BAL, or dithiothreitol protected mitochondria from organotin-induced swelling. The results suggest that low levels of active organotins may induce swelling by acting as foreign, anion specific ionophores in the inner mitochondrial membrane and that saturation of high capacity-low affinity mitochondrial binding sites by these compounds results in extensive and nonspecific alterations of the permeability of the mitochondrial membranes.

Specific solvation of carbanions of nitro compounds as the cause of their anomalous nucleophilicity in water

1. The kinetics of the reversible addition of the methyl ester ofα-nitropropionic acid (MNP) to acetaldehyde in dimethyl sulfoxide (DMSO) under the action of the components of a triethylammonium buffer solution were studied. 2. The equilibrium constant of the addition of MNP to acetaldehyde in DMSO was determined, and the value previously obtained for this constant in water was refined. 3. The rate constant of the nucleophilic addition of the carbanion of nitropropionic ester to acetaldehyde, catalyzed by the triethylammonium ion, was found. 4. The anomalous nature of the relationship of the basicity and nucleophilicity of the carbanions of the nitro compounds with respect to carbon, observed in water, is a consequence of solvation effects.

Proton exchange of triethylammonium ion in aqueous solution

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTProton exchange of triethylammonium ion in aqueous solutionEarle K. Ralph and Ernest. GrunwaldCite this: J. Am. Chem. Soc. 1967, 89, 12, 2963–2967Publication Date (Print):June 1, 1967Publication History Published online1 May 2002Published inissue 1 June 1967https://doi.org/10.1021/ja00988a028RIGHTS & PERMISSIONSArticle Views144Altmetric-Citations17LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (590 KB) Get e-Alerts Get e-Alerts