3400-09-7Relevant articles and documents
The mechanism of monochloramine disproportionation under acidic conditions
Fehér, Péter Pál,Purgel, Mihály,Lengyel, Adrienn,Stirling, András,Fábián, István
, p. 16713 - 16721 (2019/11/19)
Monochloramine is a widely employed agent in water treatment technologies. However, its utilization has some drawbacks like the transformation of the active species into the undesired dichloramine. Although it is more pronounced in acidic solutions, the f
AQUEOUS SOLUTIONS CONTAINING CHLORAMINE WHICH ARE FREE FROM DI-AND TRICHLOROAMINE, AS WELL AS FROM AMMONIA
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Page/Page column 3-4, (2008/12/04)
The combination of N-chlorotaurine, preferably in the form of sodium salt, and ammonium chloride in aqueous solution absent a buffer is a powerful antiseptic preparation sufficiently stable for use in topical treatment of infections, inflammation and oozing tissue deficiencies. The outstanding microbicidal properties of the preparation are founded in the formation of monochloramine, which is distinguished by the absence, or substantial absence, of dichloramine and trichloramine.
Method and apparatus for producing synergistic biocide
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Page/Page column 6-7, (2008/06/13)
An apparatus and methods to produce synergistic mixtures (or combinations) of haloamines to control growth of microorganisms in aqueous systems are disclosed. The apparatus and methods to produce synergistic mixtures entails producing a batch quantity of a haloamine and converting part of the haloamine to a second haloamine species to form the synergistic mixture.
Electrochemical behavior of chloramines on the rotating platinum and gold electrodes
Piela, Barbara,Wrona, Piotr K.
, p. E255-E265 (2008/10/08)
Electroreduction of chloramines (mono-, di-, and trichloramine) in 1 M NH4Cl solutions of different pH was investigated at the rotating platinum and gold electrodes. It was found that all chloramines are present in the solution in nonprotonated forms and give well-formed one-step or two-step current-potential waves. The final products of reduction are ammonium (or ammonia) and chloride ions. Monochloramine is reduced in a single two-electron irreversible wave. Hydrazine is not an intermediate in monochloramine reduction. Dichloramine reduction generally proceeds in two two-electron steps (via monochloramine). Below pH 4.3 a kinetic current due to the protonated dichloramine reduction (single four-electron wave) is in force, appearing as an increase of the height of the first step on lowering pH. Due to this process below pH 2.5 only one four-electron reduction wave is observed. Trichloramine reduction occurs in two steps: two-electron trichloramine to dichloramine reduction and four-electron dichloramine reduction. In strong acidic solutions the kinetic current due to the protonated trichloramine reduction has to be taken into account. A reaction mechanism common for all chloramines was proposed with [NXCl·] as an intermediate (X = H2, HCl, and Cl2 for mono-, di-, and trichloramine, respectively). The rate-determining step does not involve proton transfer.
BICYCLIC NONANE AND DECANE COMPOUNDS HAVING DOPAMINE RECEPTOR AFFINITY
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, (2008/06/13)
Described herein are D4 receptor-selective compounds of the general formula: STR1 wherein: A and B are independently selected, substituted or unsubstituted, unsaturated 5-or 6-membered, homo-or heterocyclic rings;X 1 is selected from O, S, SO, SO 2, CH. sub.2, C=O, CH--OH, CH--N(C 1-4 alkyl) 2, C= CHCl, and C=CHCN;X 2---is selected from N= , CH. sub.2--, CH= and C(O)--;n is 1 or 2; R 1 is selected from H and the α-carbon side chain of an amino acid;R 2 and R 3 are selected independently from H, OH,--NH 2,--C(O)NH 2 =O, =S,halo, cyano, C 1-9 alkyl, C 1-9 alkoxy, C 1-4 alkylS--, C 1-4 alkylSO--, C 1-4 alkylSO 2--, phenoxy, benzyloxy and piperonyloxy; andH* is in either the R-or the S-configuration,and acid addition salts, solvates and hydrates thereof.Their use as ligands for dopamine receptor identification and in a drug screening program, and as pharmaceuticals to treat indications in which the D4 receptor is implicated, such as schizophrenia, is also described.
BICYCLIC NONANE AND DECANE COMPOUNDS HAVING DOPAMINE RECEPTOR AFFINITY
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, (2008/06/13)
Described herein are D4 receptor-selective compounds of the general formula: STR1 wherein: A and B are independently selected, optionally substituted, saturated or unsaturated 5-or 6-membered, homo-or heterocyclic rings;X 1 is selected from CH 2, O, NH, S, C=O, CH--OH, CH--N(C 1-4 alkyl) 2, C=CHCl, C= CHCN, N-C 1-4 alkyl, N-acetyl, SO 2 and SO;X. sub.2---is selected from N=, CH 2--, CH=, C(O)--, O--, and S--;n is 1 or 2;R 1 is selected from H and an amino acid side chain;R 2 is selected from H, OH, C 1-9 alkyl, C 1-9 alkoxy, and benzyloxy; andR 3 is selected from H, OH, halo, cyano, C 1-4 alkyl, C 1-4 alkoxy, phenoxy, benzyloxy, =O, =S, C 1-4 alkylsulfonyl, C 1-4 alkylsulfonyl, C 1-4 alkylthio, amino, and aminocarbonyl;and acid addition salts, solvates and hydrates thereof. Their use as ligands for dopamine receptor identification and in a drug screening program, and as pharmaceuticals to treat indications in which the D4 receptor is implicated, such as schizophrenia, is also described.
Non-metal redox kinetics: Oxidation of bromide ion by nitrogen trichloride
Gazda, Michael,Kumar, Krishan,Margerum, Dale W.
, p. 3536 - 3542 (2008/10/08)
Bromide ion reacts with NCl3 to generate NBrCl2 with the rate expression d[NCl3]/dt = 12[Br-][NCl3] (M s-1 at 25.0°C, μ = 0.50 M). The NBrCl2 intermediate subsequently reacts with Br- to give N2, Br2, and Cl- with the rate expression -d[NBrCl2]/dt = (0.05 + 5.3[Br-])[NBrCl2]. The overall stoichiometry from pH 3.2 to 6.5 corresponds to 2NCl3 + 6Br- → N2 + 3Br2 + 6Cl-. Rate constants for NCl3 reactions show extreme sensitivity to nucleophilic strength with SO32- > CN- > I- ? Br-. Aqueous absorption spectra are determined for NCl3 with maxima at 336 nm (∈ 190 M-1 cm-1) and 220 nm (∈ 5320 M-1 cm-1) and for NBrCl2 with a maximum at 228 nm (∈ 4800 M-1 cm-1). Spectral bands for NCl3, NBrCl2, NBr2Cl, and NBr3 shift systematically with the number of bromine atoms from 220 to 256 nm. The rate constants for the reactions of NHCl2 with Br2, HOBr, and Br- are much larger than that for the reaction of NCl3 with Br-.
Non-metal redox kinetics: Reactions of trichloramine with ammonia and with dichloramine
Yiin, Boudin S.,Margerum, Dale W.
, p. 2135 - 2141 (2008/10/08)
Trichloramine reacts with excess NH3 and base (B) with the rate expression -d[NCl3]/dt = 2kB[B][NH3][NCl3], based on the overall stoichiometry 2NCl3 + 3NH3 + 3OH- → 3NH2Cl + N2 + 3Cl- + 3H2O. The reaction is general-base assisted with kB values (M-2 s-1, 25.0°C, μ = 0.50 M) of 4.46 × 103 for OH-, 3.3 × 103 for PO43-, and 22 for NH3. A water path with kH2O = 2.2 M-1 s-1 and an acidic phosphate path for H2PO4- (kHB = 450 M-2 s-1) are also found. The rate-determining step in the proposed mechanism is a Cl+ transfer between NCl3 and NH3 to give HNCl2 and NH2Cl. This is followed by N2 formation in a rapid base-assisted reaction between NCl3 and HNCl2 with the rate expression -d[NCl3]/dt = kB′[B][HNCl2][NCl3], based on the stoichiometry NCl3 + HNCl2 + 3OH- → N2 + 2HOCl + 3Cl- + H2O. Values of kB′ (M-2 s-1, 25.0°C, μ = 0.50 M) are 2.92 × 104 for HPO42- and greater than 4 × 107 for OH-. The HOCl released in the formation of N2 reacts with excess NH3 to give more NH2Cl, which accounts for the overall stoichiometry of 1.5 NH2Cl formed per NCl3. The reaction between NCl3 and HNCl2 is of critical importance in the explanation of breakpoint chlorination processes.
Non-metal redox kinetics: Reactions of sulfite with dichloramines and trichloramine
Yiin, Boudin S.,Margerum, Dale W.
, p. 1942 - 1948 (2008/10/08)
Pulsed-accelerated-flow (PAF) and stopped-flow techniques are used to study the kinetics of HNCl2 and CH3NCl2 reactions with sulfite. Pseudo-first-order rate constants with excess sulfite at p[H+] 3.7-6.4 are measured from 35-45000 s-1 (25.0°C, μ = 0.50). Acid suppresses the rate because SO3H- is much less reactive than SO32-. The rate expression is -d[RNCl2]/dt = k1[RNCl2][SO32-], where k1 (M-1 s-1) is 5.8 × 106 for HNCl2 and 2.4 × 107 for CH3NCl2. The initial nitrogen product is RNHCl, which reacts further with sulfite. Trichloramine reactions with sulfite are measured by the PAF method under second-order conditions with unequal concentrations (25.0°C, μ = 0.50) from p[H+] 3.8 to 4.6. The rate expression is -d[NCl3]/dt = (k1[SO32-] + k2[SO3H-])[NCl3], where k1 is 4.5 × 109 M-1 s-1 and k2 is 1.4 × 107 M-1 s-1. The initial nitrogen product is HNCl2, which reacts further with sulfite. A Cl+-transfer mechanism is proposed for all the reactions with sulfite to give ClSO3- as an initial product that hydrolyzes to give Cl- and SO42-. The relative reactivities of active chlorine species with SO32- are NCl3 ? HNCl2 ? NH2Cl ? OCl-, where the NCl3 and HNCl2 reactions are suppressed by acid whereas the NH2Cl and OCl- reactions are acid assisted.
Non-metal redox kinetics: Oxidation of iodide by hypochlorous acid and by nitrogen trichloride measured by the pulsed-accelerated-flow method
Nagy, Julius C.,Kumar, Krishan,Margerum, Dale W.
, p. 2773 - 2780 (2008/10/08)
The very rapid reaction between HOCl and I- is general-acid- (HA-) assisted. The proposed mechanism is HOCl + I- ?k-1k1 HOClI- HOClI- →k0 HO- + ICl HOClI- + HA →kHA H2O + ICl + A- ICl + 2I- →fast I3- + Cl- where a stability constant (k1/k-1 = 220 M-1) is determined for the HOClI- intermediate from kinetic data and the limiting rate constant at high [H+] is k1 = 4.3 × 108 M-1 s-1. Values for third-order rate constants (with the general form k1kHA/(k0 + k-1) (M-2 s-1) at 25.0°C, μ = 0.1) are evaluated for H3O+ (3.5 × 1011), CH3COOH (3.2 × 1010), and H2PO4- (2.6 × 1010) and give a Br?nsted α value of 0.11, which indicates a small degree of proton transfer in the transition state. For the H2O path, k0k1/(k0 + k-1) = 1.4 × 108 M-1 s-1. The reaction between trichloramine and iodide exhibits saturation kinetics due to the formation of NCl3I- (K1 = 6 × 103 M-1), which undergoes first-order decomposition (k2 = 1.5 × 104 s-1 at 25.0°C and μ = 0.1) to HNCl2 and ICl. Acids do not affect the rate of NCl3I- decomposition. For these two studies first-order rate constants fall in the range of 10 000-142 000 s-1 and are measured by pulsed-accelerated-flow spectroscopy.
