14609-74-6Relevant articles and documents
Thermodynamic origin of the increased rate of hydrolysis of phosphate and phosphorothioate esters in DMSO/water mixtures
Sorensen-Stowell, Kerensa,Hengge, Alvan C.
, p. 7180 - 7184 (2006)
The hydrolysis rates of the dianions of phosphate and phosphorothioate esters are substantially accelerated by the addition of polar aprotic solvents such as DMSO and acetonitrile. The activation barrier ΔG? is smaller due to a lower enthalpy of activatio
Synthesis of hydroxylated group IV metal oxides inside hollow graphitised carbon nanofibers: Nano-sponges and nanoreactors for enhanced decontamination of organophosphates
Astle, Maxwell A.,Rance, Graham A.,Fay, Michael W.,Notman, Stuart,Sambrook, Mark R.,Khlobystov, Andrei N.
, p. 20444 - 20453 (2018)
The confinement and enhanced catalytic properties of hydroxylated group IV metal oxide nanostructures inside hollow graphitised carbon nanofibers (GNF) has been demonstrated. GNF-a structural analogue of carbon nanotubes-were effectively filled with suitable precursor molecules of metal chlorides from the gas and liquid phases. Subsequent base-catalysed hydrolysis afforded amorphous, nanostructured hydroxylated metal oxide (MOx(OH)y where M = Zr, Ti, and Hf) thin films, which coat the internal surfaces of GNF. This versatile and general strategy allows the chemical composition and morphology of the encapsulated material to be modified by varying the conditions used for hydrolysis and post-synthesis thermal treatment. The increased Lewis acidic properties and high surface area of the zirconium composite promote the catalysed hydrolysis of dimethyl nitrophenyl phosphate (DMNP)-a toxic organophosphorus chemical. A four-fold enhancement in the rate of DMNP hydrolysis relative to its separate constituent components was observed, highlighting the surprising synergistic abilities of this composite material to perform both as a 'nano-sponge', absorbing the harmful compounds inside the GNF, and a nanoreactor, enhancing the local concentration of organophosphate around the hydroxylated metal oxide species, leading to improved catalytic performance.
Cetylpyridinium bromide-based oil-in-water microemulsions as a medium for hydrolysis of esters of phosphorus acids in the presence of primary amines
Mirgorodskaya,Kudryavtseva,Zuev,Idiyatullin,Fedotov
, p. 245 - 249 (2001)
High-resolution 1H NMR technique with Fourier-transform and pulsed-gradient spin-echo was used to study the structure of oil-in-water microemulsions based on cetylpyridinium bromide. The sizes of microdrops and the distribution of components between the disperse and continuous phases were found. It was shown for the hydrolytic decomposition of O,O-bis-(p-nitrophenyl) methyl phosphonate in the presence of amines that the microemulsion medium can affect both the rate and mechanism of hydrolysis. The reaction rate constants depend on the structure of microdrops.
Supramolecular systems based on aminomethylated calix[4]resorcinarene and a cationic surfactant: Catalysts of the hydrolysis of esters of phosphorus acids
Kashapov,Pashirova,Zhiltsova,Lukashenko,Ziganshina,Zakharova
, p. 200 - 204 (2012)
Kinetics of alkaline hydrolysis of 4-nitrophenyl esters of tetracoordinated phosphorus acids in micellar solutions of aminomethylated calix[4]resorcinarene containing sulfonatoethylene groups on the lower rim of the macrocycle, 4-aza-1-hexadecyl-azoniabicyclo[2.2.2]octane bromide and their mixtures was investigated spectrophotometrically. It is established that the catalytic effect of aggregates depends on the concentration of calixarene and surfactants, pH, presence of lanthanum salt and reaches more than two orders of magnitude. The parameters of the catalyzed reactions and their dependence on the composition are determined.
Synthesis and phosphatase activity of a Cobalt(II) phenanthroline complex
Garai, Mamoni,Dey, Dhananjay,Yadav, Hare Ram,Maji, Milan,Choudhury, Angshuman Roy,Biswas, Bhaskar
, p. 1513 - 1520 (2017)
Abstract: A mononuclear cobalt(II) complex, [Co (phen) 2Cl 2], (phen = 1,10-phenanthroline) has been synthesized and structurally characterized by different spectroscopic methods including single crystal X-ray structural study. X-ray
Metallomicellar hydrolytic catalysts containing ligand surfactants derived from alkyl pyridin-2-yl ketoxime
Cibulka, Radek,Dvorak, David,Hampl, Frantisek,Liska, Frantisek
, p. 1342 - 1354 (1997)
N-Hexyl-(2a), N-octyl-(2b), N-decyl-(2c) and N-dodecyl-N-[2-(hydroxyimino)-2-(pyridin-2-yl)-ethyl]dimethylammonium (2d) nitrates were synthesized as water-soluble cationic ligand surfactants. Three types of micellar catalytic systems employing salts 2 were prepared: homomicellar water solutions of salts 2, comicellar solutions of salts 2 wilh an inert cationic tenside hexadecyltrimethylammonium bromide (CTAB) and comicellar systems consisting of complexes of ligand surfactants 2 with transition metal ions (Co(II), Ni(II), Cu(II) and Zn(II)) and CTAB. Hydrolytic efficiency of all micellar and metallomicellar systems was tested by measuring the kinetics of the model substrate cleavage under pseudo-firsl-order reaction conditions. Of the above-mentioned catalysts, comicellar systems of salts 2 comicellized with CTAB were most efficient. In all cases, with the exception of Zn(II), coordination of a metal ion decreased the hydrolytic efficiency of salts 2.
A study on a primitive artificial esterase model: Reactivity of a calix[4]resorcinarene bearing carboxyl groups
Cevasco, Giorgio,Galatini, Andrea,Pirinccioglu, Necmettin,Thea, Sergio,Williams, Andrew
, p. 498 - 504 (2008)
The host molecule octacarboxymethyl calix[4]resorcinarene 1 catalyses the hydrolysis of substituted phenyl N-methylpyridinium-4-carboxylate esters 3a-f by complexation followed by intracomplex reaction via an anhydride intermediate. The reactivity in the
One Step Backward Is Two Steps Forward: Enhancing the Hydrolysis Rate of UiO-66 by Decreasing [OH-]
Katz, Michael J.,Klet, Rachel C.,Moon, Su-Young,Mondloch, Joseph E.,Hupp, Joseph T.,Farha, Omar K.
, p. 4637 - 4642 (2015)
The rapid destruction of chemical threats, such as phosphate-based nerve agents, is of considerable current interest. The hydrolysis of the nerve-agent simulant methylparaoxon, as catalyzed by UiO-66 and UiO-67, was examined as a function of pH. Surprisingly, even though typical phosphate-ester hydrolysis mechanisms entail nucleophilic attack of the simulant by aqueous hydroxide, the rate of hydrolysis accelerates as the solution pH is lowered. The unexpected behavior is attributed to a pH-dependent composition change followed by ligand substitution at the Zr6-based node.
Structural, electrochemical, phosphate-hydrolysis, DNA binding and cleavage studies of new macrocyclic binuclear nickel(ii) complexes
Anbu, Sellamuthu,Kandaswamy, Muthusamy,Varghese, Babu
, p. 3823 - 3832 (2010)
New macrocyclic binuclear nickel(ii) complexes have been synthesized by using the bicompartmental mononuclear complex [NiL] [3,30-((1E,7E)-3,6-dioxa-2, 7-diazaocta-1,7-diene-1,8-diyl)bis(3-formyl-5-methyl-2-diolato)nickel(ii)] with various diamines like 1
Supramolecular catalytic systems based on 1, 4-diazabicyclo[2.2.2]octane, its alkylated quaternary derivatives, and lanthanum nitrate
Zhiltsova,Lukashenko,Pashirova,Zakharova, L. Ya.,Konovalov
, p. 2690 - 2696 (2015)
Spectrophotometry was used to study the catalytic effects of the systems composed of N-monoand N, N-dialkylated 1, 4-diazabicyclo[2.2.2]octanes and lanthanum nitrate on the hydrolysis rate of O-alkyl O-4-nitrophenyl chloromethylphosphonates (Alk = Et, Bun, and n-hexyl). The mechanism of action and efficiency of the catalytic system depend on the structure of the heterocycle, its propensity to aggregation and complexation with the lanthanum cation, and the relative content of the components in solution. The maximum catalytic effect (a ～115-fold increase in the hydrolysis rate constant) was achieved in micellar solutions of the cationic monoalkylated derivative of 1, 4-diazabicyclo[2.2.2]octane and lanthanum nitrate.
