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Trimethylammonium bromide

Bromination of the diphenyl indole derivative 316 with bromine in DMF or trimethylammonium bromide afforded the 7-bromo derivative 317. Reaction with allyl bromide or its derivatives gave A-allyl derivatives 318 that upon cyclization with palladium acetate gave 7,9-dimethoxy-l,2-diphenylpyrrolo[3,2,l-// ]quinoline derivatives 319 (92T7601) (Scheme 57). [Pg.111]

Pentaerythrityltetrakisftrimethylammonium Bromide) ([2,2-Bis(dime thy laminomethyl) trimethylene j bisf trimethylammonium Bromide], Dimethobromide [name preferred by CA]). C17H44Br4N4,mw 624.18 prepd by heating... [Pg.604]

The physical meaning of the g (ion) potential depends on the accepted model of an ionic double layer. The proposed models correspond to the Gouy-Chapman diffuse layer, with or without allowance for the Stem modification and/or the penetration of small counter-ions above the plane of the ionic heads of the adsorbed large ions. " The experimental data obtained for the adsorption of dodecyl trimethylammonium bromide and sodium dodecyl sulfate strongly support the Haydon and Taylor mode According to this model, there is a considerable space between the ionic heads and the surface boundary between, for instance, water and heptane. The presence in this space of small inorganic ions forms an additional diffuse layer that partly compensates for the diffuse layer potential between the ionic heads and the bulk solution. Thus, the Eq. (31) may be considered as a linear combination of two linear functions, one of which [A% - g (dip)] crosses the zero point of the coordinates (A% and 1/A are equal to zero), and the other has an intercept on the potential axis. This, of course, implies that the orientation of the apparent dipole moments of the long-chain ions is independent of A. [Pg.41]

Ethoxylated methylcarboxylates Propoxyethoxy glyceryl sulfonate Alkylpropoxyethoxy sulfate as surfactant, xanthan, and a copolymer of acrylamide and sodium 2-acrylamido-2-methylpropane sulfonate Carboxymethylated ethoxylated surfactants (CME) Polyethylene oxide (PEG) as a sacrificial adsorbate Polyethylene glycols, propoxylated/ethoxylated alkyl sulfates Mixtures of sulfonates and nonionic alcohols Combination of lignosulfonates and fatty amines Alkyl xylene sulfonates, polyethoxylated alkyl phenols, octaethylene glycol mono n-decyl ether, and tetradecyl trimethyl ammonium chloride Anionic sodium dodecyl sulfate (SDS), cationic tetradecyl trimethyl ammonium chloride (TTAC), nonionic pentadecylethoxylated nonylphenol (NP-15), and nonionic octaethylene glycol N-dodecyl ether Dimethylalkylamine oxides as cosurfactants and viscosifiers (N-Dodecyl)trimethylammonium bromide Petrochemical sulfonate and propane sulfonate of an ethoxylated alcohol or phenol Petrochemical sulfonate and a-olefin sulfonate... [Pg.198]

A kinetic study of the thermal degradation of cetyl-trimethylammonium bromide inside the mesoporous SBA-3 molecular sieve... [Pg.225]

Phenylene-bridged periodic mesoporous organosilicas, with both amorphous and crystal-like walls, (referred to in the following as AW-Ph-HMM and CW-Ph-HMM, respectively) were synthesized and characterized as previously reported [6,7]. BTEB was used as a precursor for both solids the surfactant was Brij-76 (Ci8H37(OCH2CH2)nOH) in acidic media for AW-Ph-HMM and octadecyl-trimethylammonium bromide(ODTMA) in basic media for CW-Ph-HMM. A purely siliceous MCM-41 sample was also synthesised, the first step being the solution of octadecyltrimethylammonium bromide in a basic aqueous solution (NH3), kept a 333 K. Tetraethyl orthosilicate (TEOS) was then added in all cases dropwise, and the mixture stirred for 24h at room temperature (H20 34.2 g/ NH3 (15%) 8.52 g/ ODTMA 0.73 g TEOS 3.24 g). After further 24 hours in hydrothermal conditions at 368 K, the sample... [Pg.233]

Polybutylacrylate-co-Methacryloxyethyl Trimethylammonium Bromide (80/20) 1.0-5.0 Polysciences, Warrington, PA... [Pg.8]

Polyb utylacryl ate- co -Meth acryoxyethyl Trimethylammonium Bromide 9 20... [Pg.40]

Saunders and co-workers (Amin et al., 1990) used E2 elimination reactions in the p-substituted 2-phenylethyl system to test the new criteria for tunnelling suggested by the above calculations. The actual substrates and base/solvent systems they used were (2-phenylethyl-2-f)-trimethylammonium bromide, [19], with sodium ethoxide in ethanol, 2-phenylethyl-2-f bromide, [20], with potassium t-butoxide in t-butyl alcohol and 2-(p-chlorophenyl)ethyl-2-f tosylate, [21], with potassium t-butoxide in t-butyl alcohol. When equation (57) was applied to the experimental secondary (kB/ S) KIEs in Table 39, the calculated /th h KIEs were 1.106 0.033 and 1.092 0.026 for [19] and [21],... [Pg.225]

Bromomethylation of arenes using 1,3,5-trioxane and hydrobromic acid is catalysed by the addition of a phase-transfer catalyst. Yields in excess of 90% are attained using (tetradecyl)trimethylammonium bromide under relatively mild conditions for a range of arenes [55]. Tetra-n-butylammonium bromide is ineffective, suggesting the catalytic effect may be micellar. [Pg.65]

H. Chaimovich, V. R. Correia, P. S. Araujo, M. V. Aleixo, I. M. Cuccovia, A Quantitative Analysis of the Effect of Hexadecyl-Trimethylammonium Bromide Micelles on the Rate of Alkaline Hydrolysis of Benzylpenicillin , J. Chem. Soc., Perkin Trans. 2 1985, 925-928. [Pg.249]

The application of the activity of the surfactant has been examined also for the surface tension and adsorption of disodlum alkyl phosphate(6,7), sodium dodecyl sulfate(37), alkyl trimethylammonium bromide(35 ), and sodium perfluorooctanoate(13) solutions. These studies show that the surface tension and theadsorption amount are controlled by the activity of surfactant, irrespective of the added electrolyte concentration. [Pg.83]

Ci2H25S0itNa (NaDDS) from B.D.H. or Serva (Germany) Na-deoxy-cholate (NaDOC) from Sigma Cetyl trimethylammonium bromide (CTAB) from Schuchardt, were used as supplied by the respective manufacturer (over 99 % purity). Distilled water was used after treatment with the Millipore Q filter. [Pg.333]

The effects of micelles of cetyltrimethylammonium bromide (CTABr), tetradecyl-trimethylammonium bromide (TTABr) and sodium dodecyl sulfate (SDS) on the rates of alkaline hydrolysis of securinine (223) were studied at a constant [HO ] (0.05 m). An increase in the total concentrations of CTABr, TTABr and SDS from 0.0 to 0.2 M causes a decrease in the observed pseudo-first-order rate constants (kobs) by factors of ca 2.5, 3, and 7, respectively. The observed data are explained in terms of pseudophase and pseudophase ion-exchange (PIE) models of micelles. Cationic micelles of CTABr speed attack of hydroxide ion upon coumarin (224) twofold owing to a concentration effect. ... [Pg.75]

Currently available BAS include cholestyramine, colestipol and colesevelam hydrochloride (colestimide). Cholestyramine comprises a long-chain polymer of styrene with divinylbenzene trimethylbenzylammonium groups, whereas colestipol is a long-chain polymer of l-chloro-2,3-epoxypropane with diethylenetriamine. Colesevelam HCl is poly(allylamine hydrochloride) cross-linked with epichlorohydrin and alkylated with 1-bromodecane and 6-bromo-hexyl-trimethylammonium bromide. Bile-acid binding is enhanced and stabilised in the latter compound by long hydrophobic sidechains, increased density of primary amines, and quaternary amine sidechains. For this reason, colesevelam HCl exhibits increased affinity, specificity and capacity to bind bile acids compared with the other BAS. Colesevelam HCl also binds dihydroxy and trihydroxy bile acids with equal affinity, contrasting with cholestyramine and colestipol that preferentially bind dihydroxy bile acids (CDCA and deoxycholic acid). The latter BAS can lead to an imbalance towards trihydroxy bile acids and a more hydrophilic bile-acid pool. [Pg.134]

Acid detergent fibre (ADF) Cetyl trimethylammonium bromide in 0.5 M H.SO, Boil for 1 h Lignocellulose + insoluble mineral... [Pg.39]

Acid detergent solution - add 100 g cetyl trimethylammonium bromide (CTAB), also called hexadecyltrimethylammonium bromide, technical grade, to 2.5 I of 1 M sulphuric acid, stir to dissolve and make up to 5 I... [Pg.125]


See other pages where Trimethylammonium bromide is mentioned: [Pg.154]    [Pg.446]    [Pg.446]    [Pg.569]    [Pg.227]    [Pg.169]    [Pg.166]    [Pg.256]    [Pg.14]    [Pg.26]    [Pg.29]    [Pg.809]    [Pg.232]    [Pg.613]    [Pg.278]    [Pg.542]    [Pg.190]    [Pg.191]    [Pg.105]    [Pg.283]    [Pg.30]    [Pg.398]    [Pg.14]    [Pg.162]    [Pg.217]    [Pg.164]    [Pg.437]    [Pg.407]    [Pg.407]    [Pg.550]   
See also in sourсe #XX -- [ Pg.317 ]




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Trimethylammonium

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