N-Hexadecyltrimethylammonium bromide

MCM-41 spheres were prepared modifying the procedure reported by Grim et. al. [9], using n-hexadecyltrimethylammonium bromide (Ci6TMABr) as surfactant template. Reactant molar ratio was 1 TEOS 0,3 C TMABr 0,129 NH3 144 H20 58 EtOH with pH about 9. The surfactant (Ci6TMABr) was dissolved into the mixture of distilled water, NH3 and EtOH tetraethylorthosilicate ([C2H50]4Si, TEOS) was then added to the surfactant solution and stirred for 2 hours at room temperature. 

CTABr(OH) n-Hexadecyltrimethylammonium bromide (hydroxide) or cetyltrimethylammonium bromide (hydroxide)... 

Silica MCM-41 was synthesized hydrothermally at 373 K for 7 days by using water glass and n-hexadecyltrimethylammonium bromide in a manner similar to that reported by Beck et al. [2]. The quality of MCM-41 prepared here was examined by the measurements of XRD, specific surface area and pore size distribution (calculated from N2 adsorption isotherm), and TEM. 

Hexadecylpyridinium chloride, cetylpyridinium chloride n-Hexadecyltrimethylammonium bromide (hydroxide) or cetyltrimethylammonium bromide (hydroxide) Stoichiometric concentration of surfactant (detergent) Concentration of micellized surfactant generally [D ] = [D]-cwc... 

An interesting example of extension of the size of micelles is provided by the system composed of hexadecyltrimethylammonium bromide acting as a surfactant, to which n-alkane acting as solubilizing agent was added [29]. 

A paired-ion, reversed-phase high-performance liquid chromatographic method was developed for the simultaneous determination of sweeteners (dulcin, saccharin-Na, and acesulfame-K), preservatives (sodium dehydroacetate, SA, salicyclic acid, BA, succinic acid, methyl-para-hydroxybenzoic acid, ethyl-para-hydroxybenzoic acid, n-propyl-para-hydroxybenzoic acid, n-butyl-para-hydroxybenzoic acid, and isobutyl-para-hydroxybenzoic acid), and antioxidants (3-tertiary-butyl-4-hydroxyanisole and tertiary-butyl-hydroquinone). A mobile phase of acetonitrile-50 ml aqueous tr-hydroxyisobutyric acid solution (pH 4.5) (2.2 3.4 or 2.4 3.6, v/v) containing 2.5 mM hexadecyltrimethylammonium bromide and a Clg column with a flow rate of 1.0 ml/min and detection at 233 nm were used. This method was found to be very reproducible detection limits ranged from 0.15 to 3.00 p,g. The retention factor (k) of each additive could be affected by the concentrations of hexadecyltrimethylammonium bromide and a-hydroxyisobu-tyric acid and the pH and ratio of mobile phase. The presence of additives in dried roast beef and sugared fruit was determined. The method is suitable for routine analysis of additives in food samples (81). 

It seems likely that the cationic CPC micelles, which have a large positive charge at or near the micellar surface, interact attractively with the n-molecular orbital system of benzene, and that this interaction contributes to the fact that the solubilization constant for benzene in CPC is approximately twice as large as that in SDS micelles. A preferential interaction between cationic surfactants and aromatic solutes has been reported by several groups of investigators (25-27), and recent work in our laboratory shows that 1-hexadecyltrimethylammonium bromide micelles also solubilize benzene more effectively than do the anionic alkylsulfate surfactant micelles (28). Thus, the tendency of benzene molecules to solubilize near the surface of the cationic micelles, at low XB values, may lead to a partial saturation of surface "sites" by benzene, diminishing the ability of additional benzene molecules to bind near the surface. Such an effect could be responsible for the initial increase in activity coefficient that occurs, particularly in the CPC solutions, as Xg increases. 

Abbreviations CTAB = hexadecyltrimethylammonium bromide SHDTE = sodium hexadecyl-trioxyethylene sulfate SDS = sodium dodecyl sulfate DTAB = dodecyltrimethylammonium bromide TTAB = tetradecyltrimethylammonium bromide bpy = 2,2 -bipyridyl MV- = N,N -dimethyl-4,4 -bipyridinium Rh = octadecylrhodamine DMA = A, .V-dimethylaniline. 

CE CGE CHOL CIP CPG CTAB CZE dA, dG, dC DBU DEAE DMF DMT DNP DOPE DOTMA EDTA EM EOF ESI-MS Fmoc FPE ICAM-1 Capillary electrophoresis Capillary gel electrophoresis Cholesterol Cahn-Ingold-Prelog nomenclature system for absolute configuration Controlled pore glass Hexadecyltrimethylammonium bromide Capillary zone electrophoresis Deoxyadenosine, deoxyguanosine, deoxycytosine l,8-Diazabicyc o[5.4.0]undec-7-en Diethylaminoethyl- Dimethylformamide Bis(4-methoxyphenyl)phenylmethyl-, (syn. Dimethoxytrityl-) 2,4-DinitrophenyI- Dioleylphosphatidylethanolamine N-[l-(2,3-dioleyloxy)propyl]-N, N, N-trimethylammonium chloride Ethylenediamine tetra-acetic acid Electrophoretic mobility Electro-osmotic flow Electrospray ionization mass spectrometry 9-Fluorenylmethoxycarbonyl-Fluid phase endocytosis Intracellular Adhesion Molecule-1... 

Tomasic, V., Stefanic, I., and Filipovic-Vincekovic, N., Adsorption, association, and precipitation in hexadecyltrimethylammonium bromide/sodium dodecyl snlfate mixtures. Colloid Polym. Sci, 277, 153-163 (1999). 

Cetraria islandica extract Cetraria islandicus. See Iceland moss (Cetraria islandicus) extract Cetrimide BP, Cetrimide BP, Cetrimide Cetrimide. SeeCetrimonium bromide Cetrimonium bromide CAS 57-09-0 EINECS/ELINCS 200-311-3 Synonyms CETAB Cetrimide Cetyltrimethylammonium bromide CTAB Hexadecyltrimethylammonium bromide HTAB Trimethylcetylammonium bromide N,N,N-Trimethyl-1-hexadecanaminium... 

Very efficient Michael addition reactions of amines, thiphenol and methyl acetoacetate to chalcone in water suspension have been developed." For example, stirring a suspension of powdered chalcone in a small amount of water containing n-Bu NH and a surfactant, hexadecyltrimethylammonium bromide for 2 hr gave the adduct in 98% yield. Similarly adducts were obtained with thiophenol and methyl acetoacetate (Scheme 30). 

San Andres, M. P., Otero, J. Vera, S. (2011). High performance liquid chromatography method for the simultaneous determination of a-, y- and 6-tocopherol in vegetable oils in presence of hexadecyltrimethylammonium bromide/n-propanol in mobile phase. Food Chem., 126, 1470-1474... 

Surfactants are those molecules that comprise both hydrophilic and hydrophobic groups simultaneously. The hydrophilic groups can be either ionic (e.g., -SOj, -SO3, -COOH, and -N(CHsIj) or nonionic (e.g., -0-(CH2-CH2-0) -H). As to the hydrophobic groups, the most widely used ones are the alkyl chains (-C H2 +i) and arakyl chains (-C H2 +i-C6H4-). Representative surfactants include anionic sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), sodium bis(2-ethylhexyl) sulfosuccinate, sodium stearate, cationic hexadecyltrimethylammonium bromide, and nonionic i-octophenol polyethoxylate with an average of 40 monomeric units of ethylene oxide per molecule. Such amphoteric species tend to diffuse toward the interface between the oily and aqueous phases and reside therein. 

Hexadecylpyridinium chloride 1-Hexadecylpyridinium chloride n-Hexade-cylpyridinium chloride. See Cetylpyridinium chloride Hexadecyl sodium sulfate. See Sodium cetyl sulfate Hexadecyl stearate n-Hexadecyl stearate. See Cetyl stearate Hexadecyl (sulfophenoxy) benzenesulfonic acid, disodium salt See Sodium hexadecyl diphenyl disulfonate Hexadecyl tetradecanoate. See Cetyl myristate Hexadecyltrimethylammonium bromide. See Cetrimonium bromide Hexadecyl trimethyl ammonium chloride. See Cetrimonium chloride Hexadecyl trimethyl ammonium p-toluene sulfonate. See Cetrimonium tosylate Hexadienic acid Hexadienoic acid 2/4-Hexadienoic acid. See Sorbic acid 2/4-Hexadienoic acid potassium salt. See Potassium sorbate Hexaethylene glycol. See PEG-6... 

A high performance liquid chromatographic procedure has been described [3] for the simultaneous determination of the fimgicides sodium-N-methyldithiocarbamate and methylisothiocyanate in surface waters and in sewage, based on their separation on a reversed phase column with a miscellar mobile phase (hexadecyltrimethylammonium bromide) in 1 1 v/v methanohwater buffered to pH6.8. Detection limits were 70 and Ipg dm when the analysis was performed with an ultraviolet detector at 247nm. 

The indenyl complex RuCl(ri -C9H7)(PPh3)2 (Q) (Scheme 34) also provides an efficient catalyst precursor for the a n-Markovnikov hydration of terminal alkynes in aqueous media and micellar solutions in the presence of surfactants such as sodium dodecylsulfate (SDS) or hexadecyltrimethylammonium bromide (CTAB) [124] (Scheme 35). Notably, this system can be applied to the hydration of propargyhc alcohols to selectively produce (3-hydroxyaldehydes. 

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