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Diethylenetriamine systems

I will illustrate these mechanisms with the system that we used to test them. In the diethylenetriamine system, let s say with the bromide as leaving group, diethylenetriamine ties down three positions. [Pg.100]

Many other amines are catalytic in their action. One of these, piperidine, has been in use since the early patents of Castan. 5-7 pts phr of piperidine are used to give a system with a pot life of about eight hours. A typical cure schedule is three hours at 100°C. Although it is a skin irritant it is still used for casting of larger masses than are possible with diethylenetriamine and diethylaminopropylamine. [Pg.755]

The element symbols within each formula are arranged according to a modified Hill system in which the order is metal(s), C, H and then any remaining symbols arranged alphabetically. Compounds containing two (or more) different metals appear twice (or more), being listed under each metal. Common ligand abbreviations which appear in the text have also been used in the index. These include acac (acetylacetone), bipy (2,2 -bipyridyl), diars [o-phenylenebis(dimethyl-arsine)], dien (diethylenetriamine), etc. [Pg.255]

Quatemized imidazolines with an amido moiety are suitable formulations for general oil and gas field applications. The synthesis of such compounds is detailed in the literature [1218]. For aqueous systems that contain sulfide compounds, a mixture has been described [262] that consists of an aqueous solution of an alcohol such as diethylene glycol monobutyl ether, butyl cellosolve, additional orthophosphoric acid, a fatty acid (from tall oil), substituted imidazoline, an ethoxylated fatty diamine (polyamines such as ethylenediamine, diethylenetriamine, etc.), and a molybdate compound. [Pg.96]

Stepwise formation constants have been determined in the system Hg2+/Cl-/diethylenetriamine (dien) and related systems by potentiometry. Thermodynamic parameters have been calculated and the contribution of the entropy term to complex stability discussed.208... [Pg.1273]

In mammals, phenobarbital and phenytoin increase serum ceruloplasmin concentrations (Aaseth and Norseth 1986). Chronic copper poisoning in sheep is exacerbated when diets contain heliotrope plants (Heliotropium sp., Echium spp., Senecio sp.). Aggravated effects of the heliotrope plants include reduced survival and a twofold to threefold increase in liver and kidney copper concentrations when compared to control animals fed copper without heliotropes (Howell et al. 1991). Rats given acutely toxic doses of 2,3,7,8-tetrachlorodibenzo-para-dioxin had elevated concentrations of copper in liver and kidney because of impaired biliary excretion of copper (Elsenhans et al. 1991). Morphine increases copper concentrations in the central nervous system of rats, and dithiocarbam-ates inhibit biliary excretion (Aaseth and Norseth 1986). In human patients, urinary excretion of copper is increased after treatment with D-penicillamine, calcium disodium EDTA, or calcium trisodium diethylenetriamine penta acetic acid (Flora 1991). [Pg.139]

Chan, H-K., Daviskas, E., Eberl, S., Robinson, M., Bautovich, G., and Young, I.H., Deposition of aqueous aerosol of technetium-99m diethylenetriamine pentaacetic acid generated and delivered by a novel system (AERx) in healthy subjects, Eur. J. Nucl. Med., 26 320-327 (1999). [Pg.268]

Kinetic studies of various systems have been carried out as follows the reaction of 2,2 -dichlorodiethyl sulfide and of 2-chloroethyl ethyl sulfide with diethylenetriamine and triethylamine in 2-methoxyethanol ° the catalysed reactions of substituted phenols with epichlorohydrin the reactions of para-substituted benzyl bromides with isoquinoline under high pressure the reactions of O-alkylisoureas with OH-acidic compounds [the actual system was N, N -dicyclohexyl-0-(l-methylheptyl)isourea with acetic acid] and tlie ring opening of isatin in aqueous binary mixtures of methanol and acetonitrile cosol vents. [Pg.344]

In the condensed chelate systems, many kinds of chelating agents were used, such as ethylenediamiiie-/V,/V,/V, /V -tetraacetic acid (EDTA), nitrilotriacetic acid (NTA), /-aspartic acid (AA), trimethylenediamine (TMD), /V,/V-dimethylethylenedi-amine (DMED), diethylenetriamine (DETA), triethylenetetraamine (TETA), and t ris(2-aminoethyl)amine (TAEA) (6). The chelating agents used are listed in Table 3.2.1. [Pg.199]

Fig. 25. Photopotentials of systems amine/thionine (TH) as function of the number of amino or imino groups (A-groups) per molecule of the amine. [TH] = 10 5 mol/1 [A-groups] --= 5 10-3 mol/1 pH 8. DEA Diethylamine, DEen N,N -diethylethylene-diamine, dien Diethylenetriamine, trien Traethy-lenetetramine, tetraen Tetraethylenepentamine, PEI Poly(ethyleneimine)... Fig. 25. Photopotentials of systems amine/thionine (TH) as function of the number of amino or imino groups (A-groups) per molecule of the amine. [TH] = 10 5 mol/1 [A-groups] --= 5 10-3 mol/1 pH 8. DEA Diethylamine, DEen N,N -diethylethylene-diamine, dien Diethylenetriamine, trien Traethy-lenetetramine, tetraen Tetraethylenepentamine, PEI Poly(ethyleneimine)...
A three-site system for peptide synthesis around a cobalt(III) complex has been studied. Instead of a quadridentate ligand as used in the above experiments, Wu and Busch chose the tridentate ligand diethylenetriamine. The formation of dipeptide and tetrapeptide complexes is shown in Scheme 92.360 The ester carbonyl group in the 0-bonded amide intermediate (127) cannot be activated by coordination because it cannot reach the metal ion. Isomerization to the jV-bonded amide complex (128) occurs with base and enables coordination and therefore activation of the ester carbonyl group. [Pg.215]

Based on the screening results, 27 diethylenetriamines and 24 N-methyl-1,4,5-trisubstituted 2,3-diketopiperazines were generated and assayed in the X4 and R5 systems. The most active diethylenetriamines had IC50 values varying from 30 to 500 nM and 840 nM to 1.1 gM in the R5 and X4 systems, respectively, while the most active diketopiperazines had IC50 values varying from 5 to 36 /uM in both systems. [Pg.335]

Fig. 2. Inhibitory activity of HIV-l-mediated fusion by diethylenetriamine and IV-methyl-l,4,5-trisubstituted 2,3-diketopiperazine PS-SCLs. Each bar within a graph represents the percent inhibition as measured in the X4 fusion system by a separate mixture at 2.5 /ig/ml for the diethylenetriamines and at 25 /ig/ml for the diketopiperazines. The line represents the average activity for all of the mixtures making up the corresponding sublibrary. Fig. 2. Inhibitory activity of HIV-l-mediated fusion by diethylenetriamine and IV-methyl-l,4,5-trisubstituted 2,3-diketopiperazine PS-SCLs. Each bar within a graph represents the percent inhibition as measured in the X4 fusion system by a separate mixture at 2.5 /ig/ml for the diethylenetriamines and at 25 /ig/ml for the diketopiperazines. The line represents the average activity for all of the mixtures making up the corresponding sublibrary.
The chemical structures of important amines for curing epoxy resins in adhesive systems are identified in Fig. 5.1. Diethylenetriamine (DETA), triethylenetetramine (TETA), ra-aminoethylpiperazine (AEP), diethylaminopropylamine (DEAPA), ra-phenylenediamine (MPDA), and diaminodiphenyl sulfone (DDS) are the most commonly used members of this class. They are all primary amines. They give room or elevated temperature cure at near stoichiometric ratios. Ethylenediamine is too reactive to be used in most practical adhesive formulations. Polyoxypropyleneamines (amine-terminated polypropylene glycols) impart superior flexibility and adhesion. [Pg.88]

Poly(ethylenimine) (PEI) has been examined extensively both in its classical, random branched topology [125] and in its linear form [126]. The various architectural and topological forms of PEI have been reviewed recently [127], Here we describe the first example of this polymer system as an ideal, hyper-branched molecular assembly. Synthesis of a tri-dendron poly(ethyleneimine) dendrimer derived from an ammonia core involved, first the selective alkylation of diethylenetriamine (DETA) with aziridine to produce a symmetrical core cell, namely tris-(-2-aminoethyl)amine. Subsequent exhaustive alkylations of the terminal amino moieties with activated aziridines [2, 127, 128], such as IV-tosyl- or N-mesylaziridine gave very good conversions to the first-generation protected... [Pg.256]

Such experiments show that oxalate, tartrate, and citrate give fairly strong complexes, and indeed these mixtures do not suffer quite such rapid oxidation as the other systems (57, 70). Stability constants for the complexing of U(III) by acetate, 2-hydroxy-2-methylpropionate, nitriloacetate, trans-cyclohexyl-1,2-diaminotetraacetate, ethylenedi-amine tetraacetate, and diethylenetriamine pentaacetate have been reported, but no pure compounds have been isolated (71). Thiocyanate also accelerates oxidation of the uranium, but the blue complex that is formed can be extracted with triethyl phosphate, tributyl phosphate, or better, trioctyl phosphine oxide the organic extract decomposes only slowly (45, 72). [Pg.74]

A chain-shape polyamine and ethylene glycol system favors the formation of layered aluminophosphates with an Al/P ratio of 3/4. For instance, ethylenediamine, diethylenetriamine, and triethylenetetramine combining with ethylene glycol solvent lead to the formation of layered aluminophosphates with an AFP ratio of 3/4 (see Table 3.9). Therefore, it is expected that using tetraethylenepentamine as template and ethylene glycol as solvent will result in the crystallization of a layered aluminophosphate with an AFP ratio of 3/4. Guided by this prediction, we did... [Pg.150]

It must be noted tliat, even with an extremely hydrophobic catalyst, catalyst-free particles would be formed by radical exit and nucleation of new particles, and thus uncontrolled polymerization would occur. On the other hand, it is also proposed that with more hydrophilic ligands (such as Meg-TREN, or pentamethyl diethylenetriamine (PMDETA) [221]) all the catalyst is located in the aqueous phase, and uncontrolled polymerization occurs in the hydrophobic polymer particles. However, these ligands are also ineffective in controlling the aqueous polymerization of water-soluble monomers (see above), hinting that ligand dissociation might also occur in these systems [215]. [Pg.265]


See other pages where Diethylenetriamine systems is mentioned: [Pg.161]    [Pg.161]    [Pg.121]    [Pg.83]    [Pg.15]    [Pg.170]    [Pg.490]    [Pg.256]    [Pg.188]    [Pg.170]    [Pg.316]    [Pg.294]    [Pg.159]    [Pg.204]    [Pg.335]    [Pg.159]    [Pg.135]    [Pg.211]    [Pg.254]    [Pg.88]    [Pg.266]    [Pg.468]    [Pg.29]    [Pg.1073]    [Pg.892]    [Pg.3095]    [Pg.166]    [Pg.476]    [Pg.168]    [Pg.177]   
See also in sourсe #XX -- [ Pg.9 ]




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Diethylenetriamine

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