Cetyltrimethylammonium chloride

Cetyltrimethylammonium chloride [112-02-7] Nl 320.0. Crystd from acetone/ether mixture, EtOH/ether, or from MeOH. [Moss et al. J Am Chem Soc 109 4363 1987.]... 

Chemical Designations - Synonyms Cetyltrimethylammonium chloride solution Chemical Formula CisH33(CH3)3NCl-HjO-(CH3)aCHOH. 

Photoinduced ET at liquid-liquid interfaces has been widely recognized as a model system for natural photosynthesis and heterogeneous photocatalysis [114-119]. One of the key aspects of photochemical reactions in these systems is that the efficiency of product separation can be enhanced by differences in solvation energy, diminishing the probability of a back electron-transfer process (see Fig. 11). For instance, Brugger and Gratzel reported that the efficiency of the photoreduction of the amphiphilic methyl viologen by Ru(bpy)3+ is effectively enhanced in the presence of cationic micelles formed by cetyltrimethylammonium chloride [120]. Flash photolysis studies indicated that while the kinetics of the photoinduced reaction,... 

The Henry (nitroaldol) reaction was reported under very mild reaction conditions, in aqueous media using a stoichiometric amount of a nitroalkane and an aldehyde, in NaOH 0.025 M and in the presence of cetyltrimethylammonium chloride (CTAC1) as cationic surfactant (Eq. 8.94) 240 Good to excellent yields of (i-nitroalkanol are obtained. Under these conditions several functionalities are preserved, and side-reactions such as retro-aldol reaction or dehydration of 2-nitroalcohols are avoided. 

The nitro-aldol reaction can also be carried out in water using NaOH in the presence of cetyltrimethylammonium chloride (CTAC1) as a cationic surfactant. CTAC1 (5 mmol) is added to a mixture of nitroalkane (50 mmol) and aldehyde (50 mmol) in NaOH 0.025 M (150 mL) at room temperature. The mixture is stirred for 2-3 h and worked up to give the product in 70-90% yield. Compared with the classical methods, this procedure has economical and environmental advantages (Eq. 3.16).27... 

In recent years, there has been increased recognition that water is an attractive medium for organic reactions from the environmental point of view. The Michael addition of various nitroalkanes to conjugated enones can be performed in NaOH (0.025 M) and in the presence of cetyltrimethylammonium chloride (CTAC1) as cationic surfactant in the absence of organic solvents (Eq. 4.109).146 The Michael addition of nitromethane to methyl acrylate is carried out in water using NaOH as a base to give the mono adduct (Table 4.2).147... 

In micelles of the surfactant cetyltrimethylammonium chloride (CTAC), the ratio of AA AB BB is <1 >98 <1 %. The CTAC micelles provide a cage effect, which greatly enhances the joining of the A and B radicals produced by the photolysis (Scheme 12.3). 

Mg(II) forms a complex with 8-hydroxyquinoline-5-sulfonic acid (37) at pH 9.0 with Tris-HCl buffer, which can be determined by ELD (X x = 388 nm, ka = 495 nm) with micellar enhancement by cetyltrimethylammonium chloride (38). Masking of Ca(II) is achieved by EGTA (19). The method was applied in a SIA system for analysis of natural waters . After elution of the Mg(II) ions adsorbed on an alkali-activated PTFE tube with 0.1 M HCl and addition of A,A -bis(salicylidene)-2,3-diaminobenzofuran (39), the end analysis was by fluorometric determination of the Mg(II) complex (kex =475 nm, kfl = 545 nm). Possible interference of Ca(II) is masked on addition of the chelating agent... 

Preparing mixture solution A Distilled H20, NaOH and surfactant (cetyltrimethylammonium chloride, CTAC) were mixed together with stirring, then adding alumina source (if synthesis of Zr (Ti)-Si-Al material, here adding alumina source + Zr (Ti)... 

Glycyrrhizin can also be determined by ion-pair chromatography (64,105). Matsunaga et al. (64) separated glycyrrhizin from saccharin on a reverse-phase column with ethanol 50 mM sodium dihydrogenphosphate (2 3, v/v) containing 20 mM cetyltrimethylammonium chloride, pH 3. 

Methyl-substituted aromatic hydrocarbons are readily oxidized by permanganate into benzoic acid derivatives.311 Toluene, p-xylene and mesitylene are respectively converted to benzoic, terephthalic and trimesic acids in ca. 90% yield by potassium permanganate in the presence of cetyltrimethylammonium chloride.321... 

Thus, C14MV2- quenches the excited state of [Ru(bipy)3]2+ with a rate constant fcq = 8 x 10s mol-1 dm3 s-1 and this is unaffected by cetyltrimethylammonium chloride (CTAC), up to concentrations of 5 x 10-2 mol dm-3, indicating that mixed CTAC/C14MV2- micelles are not formed.139 In the absence of CTAC, kb in this system is 4x 109 mol-1 dm3 s-1, but flash photolysis showed that this drops to kb s2x 107 mol-1 dm3 s-1 in micellar solution. Thus, the more hydro-phobic radical cation, C14MV+, is solubilized by CTAC micelles, which, having a positive surface, do not allow approach of the oxidized [Ru(bipy)3]3C This then gives an efficiency of 30% for the redox reaction. This study was extended by the removal of the CTAC from solution and the introduction of a Pt catalyst protected by a positively charged polysoap.138 This work is described in Section 61.5.4.7.2. 

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