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Triton hydroxide

Triton B Trade name for benzyltrimethyl-ammonium hydroxide usually as a 40% solution in methanol. A strong base, soluble in many solvents used as a catalyst. See phase transfer chemistry. [Pg.407]

Tos, Ts [(4-methylphenyl)sulfonyl3 = p-tolueoesulfbnyl), tosyl Triton B benzyltrimeihylammonium hydroxide = Blma OH", PhCHjNMej OH-... [Pg.438]

Benzyltrimethylammonium hydroxide (Triton B) [100-85-6] M 167.3, d 0.91. A 38% soln (as supplied) was decolorized (charcoal), then evaporated under reduced pressure to a syrup, with final drying at 75° and 1 mm pressure. Prepared anhydrous by prolonged drying over P2O5 in a vacuum desiccator. [Pg.131]

The ratios of these slopes for L- and D-esters are shown in Table 12. The kL/kD values of the acylation step in the CTAB micelle are very close to those in Table 9, as they should be. It is interesting to note that the second deacylation step also occurs enantioselectively. Presumably it is due to the deacylation ocurring by the attack of a zinc ion-coordinated hydroxide ion which, in principle, should be enantioselective as in the hydroxyl group of the ligand. Alternatively, the enantioselectivity is also expected when the free hydroxide ion attack the coordinated carbonyl groups of the acyl-intermediate with the zinc ion. At any rate, the rates of both steps of acylation and deacylation for the L-esters are larger than those for the D-esters in the CTAB micelle. However, in the Triton X-100 micelle, the deacylation step for the D-esters become faster than for the L-esters. [Pg.171]

A solution of benzyltrimethylammonium hydroxide (Triton B, 10ml, 40% in MeOH) was treated with aqueous HF (ca. 8.6ml, 4.7%) until the pH reached 8-7. The solvent was removed in vacuo (ca. 1 mm), and the residue was dried at 50°C/0.5 mmHgfor 20 h. The resulting highly hygroscopic solid was powdered, and then stored in a desiccator over P205. [Pg.148]

Fig. 2 Increase in the fluorescence intensity of dienestrol as a function of heating time after immersion of the chromatogram in sodium hydroxide solution (c = 1 mol/L) followed by treatment with Triton 100-X and heating to 120°C. Fig. 2 Increase in the fluorescence intensity of dienestrol as a function of heating time after immersion of the chromatogram in sodium hydroxide solution (c = 1 mol/L) followed by treatment with Triton 100-X and heating to 120°C.
The reverse microemulsion method can be used to manipulate the size of silica nanoparticles [25]. It was found that the concentration of alkoxide (TEOS) slightly affects the size of silica nanoparticles. The majority of excess TEOS remained unhydrolyzed, and did not participate in the polycondensation. The amount of basic catalyst, ammonia, is an important factor for controlling the size of nanoparticles. When the concentration of ammonium hydroxide increased from 0.5 (wt%) to 2.0%, the size of silica nanoparticles decreased from 82 to 50 nm. Most importantly, in a reverse microemulsion, the formation of silica nanoparticles is limited by the size of micelles. The sizes of micelles are related to the water to surfactant molar ratio. Therefore, this ratio plays an important role for manipulation of the size of nanoparticles. In a Triton X-100/n-hexanol/cyclohexane/water microemulsion, the sizes of obtained silica nanoparticles increased from 69 to 178 nm, as the water to Triton X-100 molar ratio decreased from 15 to 5. The cosurfactant, n-hexanol, slightly influences the curvature of the radius of the water droplets in the micelles, and the molar ratio of the cosurfactant to surfactant faintly affects the size of nanoparticles as well. [Pg.234]

The dehydrohalogenation of 1- or 2-haloalkanes, in particular of l-bromo-2-phenylethane, has been studied in considerable detail [1-9]. Less active haloalkanes react only in the presence of specific quaternary ammonium salts and frequently require stoichiometric amounts of the catalyst, particularly when Triton B is used [ 1, 2]. Elimination follows zero order kinetics [7] and can take place in the absence of base, for example, styrene, equivalent in concentration to that of the added catalyst, is obtained when 1-bromo-2-phenylethane is heated at 100°C with tetra-n-butyl-ammonium bromide [8], The reaction is reversible and 1-bromo-l-phenylethane is detected at 145°C [8]. From this evidence it is postulated that the elimination follows a reverse transfer mechanism (see Chapter 1) [5]. The liquidrliquid two-phase p-elimination from 1-bromo-2-phenylethanes is low yielding and extremely slow, compared with the PEG-catalysed reaction [4]. In contrast, solid potassium hydroxide and tetra-n-butylammonium bromide in f-butanol effects a 73% conversion in 24 hours or, in the absence of a solvent, over 4 hours [3] extended reaction times lead to polymerization of the resulting styrene. [Pg.391]

Employing the free acid, nitro-lactones of configuration (99) and/or (100) are obtained, depending on the conditions used (sodium hydroxide in water or Triton B in aqueous methanol). However, with methyl nitro-... [Pg.206]

Triton B Ammonium, benzyltrimethyl-, hydroxide (8) Benzenemethanaminium, N,N,N-trimethyl-, hydroxide (9) (100-85-6)... [Pg.160]

V,Af-Dimethylaniline A A,A, AT-Tetramethyl-p-phenylenediamine Cyclic amines 4,4 -Bipyridyl Quinoline Pyridine A-oxide Pyridinium chloride Hydroxides CsOH LiOH NaOH Triton B6 Alkylamines Ammonia Methylamine Ethylamine Propylamine Butylamine Decylamine Dodecylamine Tridecylamine Tetradecylamine Pentadecylamine Hexadecylamine Heptadecylamine Octadecylamine Tributylamine Miscellaneous Ammonium acetate Hydrazine Potassium formate Guanidine... [Pg.43]

Die Addition von 7-Nitro-4-oxo-heptansaure-methylester an Acrylnitril in methanolischer Benzyl-trimethylammonium-hydroxid (Triton B)-Losung fuhrt zu 7-/Vitro-4-oxo-decandi-saure-methylester-nitril (40% )4 ... [Pg.210]

Die Addition von Nitro-alkanen an 1 -(1 -Alkenyl)-1 -trimethylsilyloxy-cyclopropane in me-thanolischer Benzyl-trimethyl-ammonium-hydroxid-Losung (Triton B) liefert unter Ring-offnung 7-Nitro-4-oxo-alkansaure-Derivate z.B.1 ... [Pg.211]

Infrared spectra suggested that a sulfate ion coordinates to two titanium atoms as a bidentate in particles. The maximum particle size was found at Aerosol OT mole fraction of 0.35 in the mixtures. The particle size increased linearly with increasing the concentration of sulfuric acid at any Wo, but with increasing Wo the effect was the opposite at any sulfuric acid concentration. These effects on the particle size can be explained qualitatively in relation with the extent of number of sulfate ions per micelle droplet. These precursor particles yield amorphous and nanosized TiO particles, reduced by 15% in volume by washing of ammonia water. The Ti02 particles transformed from amorphous to anatase form at 400°C and from anatase form to rutile form about at 800°C. In Triton X-100-n-hexanol-cyclohexane systems, however, spherical and amorphous titanium hydroxide precursor were precipitated by hydrolysis of TiCl4 (30). When the precursor particles were calcinated,... [Pg.94]

Synthesis (Tull et al. (Merck Co.), 1975 1976) Friedel-Crafts reaction of fluorobenzene and a-bromoisobutyryl bromide gives 5-fluoro-2-methylindan-1-one, which is treated with 4-methylthiobenzylmagnesium chloride to yield 5-fluoro-2-methyl-1-(4-methylthiobenzyl)indene. Condensation with glyoxylic acid in the presence of N-benzyltrimethyl ammonium hydroxide (Triton B) gives 3-carboxy methylene-5-fluoro-2-methyl-1 -(4-methylthio-ben-zyl) indene, which is isomerized in acid to 5-fluoro-2-methyl-1-(4-methylthiobenzylidene)indene-3-acetic acid. Oxidation with hydrogen peroxide affords sulindac. [Pg.106]

Selective formation of ketones may be achieved through base-catalyzed oxidations.848 Transformation of 9,10-dihydroanthracene catalyzed by benzyltrimethy-lammonium hydroxide (Triton B)855 starts with proton abstraction ... [Pg.502]

The hydroxyl group of ethyl 2-hydroxy-4-oxo-4//-pyrimido[2,l-a]-isoquinoline-3-carboxylate (20) was methylated with methyl iodide in dry boiling acetone for 5 h in the presence of potassium carbonate, with dimethyl sulfate in methylene chloride in methanol in the presence of Triton B at 20°C for 18 h, with methyl fluorosulfonate in 2.5 M sodium hydroxide at 20°C for 5 h, and with diazomethane in a mixture of diethyl ether and methylene chloride at 20°C for 3 h to give the 2-methoxy derivative (89AJC2161). The hydroxy group of 3-hydroxymethyl-4//-pyrimido[2,l-b]-isoquinolin-4-one was alkylated and acylated with 2-(diethylamino)ethyl chloride in dimethylformamide in the presence of sodium hydroxide, and with acetic anhydride in boiling chloroform in the presence of triethylamine and a few drops of 4-dimethylaminopyridine, respectively (86EUP 166439). [Pg.216]

A modified biuret reagent was formulated (sodium tartrate replaces sodium potassium tartrate, the sodium hydroxide concentration is reduced, and potassium iodide was deleted). When the modified biuret reagent was mixed with samples containing 2% detergent (SDS or sodium cholate or Triton X-I00), it resulted in less protein-to-protein variation among six proteins. [Pg.104]

Attempts to prepare 7-(cyanomethyl)benzo[6]thiophene-4,5-quin -ones by elimination of the carbethoxy group from a corresponding 7-(carbethoxycyanomethyl) compound have failed, except in one case 273 (R = H, R = Br) affords 2-bromo-7-(cyanomethyl)benzo[6]thio-phene-4,5-quinone on treatment with Triton B (benzyltrimethyl-ammonium hydroxide).497... [Pg.320]

Several points arise from consideration of this mechanism (i) unlike alkylation of stabilized enolates, the Michael reaction regenerates a basic species and thus usually catalytic quantities of base can be utilized 7 7 12 (ii) the high acidity of the doubly activated methylene permits the use of weaker bases, e.g. simple amines (piperidine, triethylamine etc.) or hydroxides (Triton B, i.e. benzyltrimethylammoni-um hydroxide) (iii) it was recognized early that, when a full equivalent of base was used, the final more... [Pg.3]

Other base systems have been also studied, including tetraethylammonium superoxide [53], basic resins [54], Triton-B (benzyltrimethylammonium hydroxide) [55], and K2C03 in the presence of catalytic amounts of (Bu4N)I [56]. In a few cases, the use of alkyltosylates, as alkylating agents in place of alkyl halides, has been also investigated [54b, 55b, 56]. [Pg.130]

Note. (1) In a modified procedure8 using triethylene glycol as solvent and benzyltri-methylammonium hydroxide (Triton B ) as the base catalyst, the reaction may be completed in a very short time. [Pg.1101]

A solution of 20.7 g of [2R-[2a,5a(S )]]-N-[l-[5-[[2-(acetyloxy)-l-oxopropoxy]methyl]tetrahydro-2-furanyl]-l,2-dihydro-2-oxo-4-pyrimidinyl] acetamide in 100 ml of ethanol was treated with 10.0 ml of Triton B (N-benzyltrimethyl-ammonium hydroxide), and the mixture was stirred at room temperature overnight. The mixture was concentrated to 20 ml, cooled to 0°C, and the product was collected by filtration. It was washed with 10 ml of cold ethanol to give 4.48 g of 2, 3 -dideoxycytidine, melting point 215°-218°C, as an white solid. [Pg.3500]


See other pages where Triton hydroxide is mentioned: [Pg.149]    [Pg.614]    [Pg.614]    [Pg.2]    [Pg.407]    [Pg.283]    [Pg.197]    [Pg.86]    [Pg.264]    [Pg.1]    [Pg.44]    [Pg.44]    [Pg.52]    [Pg.189]    [Pg.479]    [Pg.488]   
See also in sourсe #XX -- [ Pg.283 ]

See also in sourсe #XX -- [ Pg.283 ]




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Benzyltrimethylammonium hydroxide (Triton

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Triton B (benzyltrimethylammonium hydroxide

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Tritonal

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