Tetrabutyl ammonium hydroxide

Tetrabutylammonium hydroxide Ammonium, tetrabutyl-, hydroxide (8) 1-Butanaminium, /V,/V,/V-tributyl-, hydroxide (9) (2052-49-5)... 

Synonyms Ammonium, tetrabutyl-, hydroxide 1-Butanaminium, N,N,N-tributyl-, hydroxide Tetrabutylammonium hydroxide N,N,N-Tributyl-1-butanaminium hydroxide... 

The sodium and potassium salts of glutaconaldehyde are soluble only in polar solvents such as water, dimethyl sulfoxide, N,N-dimethylformamide, pyridine, and methanol. However, the stable tetrabutylammonium salt is soluble in relatively nonpolar solvents such as chloroform and ethyl acetate. It may be prepared from the potassium salt in the following manner. In a 1-1. Erlenmeyer flask equipped with a magnetic stirring bar are placed a solution of 13.6g. (0.1 mole) of crude glutaconaldehyde potassium salt in 200 ml. of water and a solution of 33.9 g. (0.1 mole) of tetrabutyl-ammonium hydrogen sulfate in 200 ml. of ice-cold water, the pH of wliich was adjusted to 10 by adding aqueous 2M sodium hydroxide. 

Mobile phase 0.001 mol dm-3 tetrabutyl ammonium hydroxide + potassium hydrogen phthalate, pH8. Flow rate 1 cm3 min 1... 

ZSM-5 and ZSM-11 samples were prepared as previously described (11) using tetrapropy 1 ammonium hydroxide and tetrabutyl ammonium bromide, respectively. The nature and crystallinity of the materials were verified by X ray diffraction, ir spectroscopy of lattice vibrational bands ( 1 2 ), n-hexane adsorption capacity at room temperature and constraint index (13) measurements. All samples correspond to highly crystalline ZSM-5 or ZSM-11 materials. The chemical compositions of the samples as determined from chemical analysis of A1 and Na contents, are given in table 1. 

Table 5.5 Alkalimetric Assays Non-Aqueous Titrations using Tetrabutyl-ammonium Hydroxide either Titrimetrically or Potentiometrically...

How would your assay Niclosamide and Chlorthalidone using tetrabutyl-ammonium hydroxide either potentiometrically or titrimetrically by non-aqueous titrations. 

Elemental sulfur is present in most soils and sediments (especially anaerobic), and is sufficiently soluble in most common organic solvents that the extract should be treated to remove it prior to analysis by ECD-GC or GC-MS. The most effective methods available are (1) reaction with mercury or a mercury amalgam [466] to form mercury sulfide (2) reaction with copper to form copper sulfide or (3) reaction with sodium sulfite in tetrabutyl ammonium hydroxide (Jensen s reagent) [490]. Removal of sulfur with mercury or copper requires the metal surface to be clean and reactive. For small amounts of sulfur, it is possible to include the metal in a clean-up column. However, if the metal surface becomes covered with sulfide, the reaction will cease and it needs to be cleaned with dilute nitric acid. For larger amounts of sulfur, it is more effective to shake the extract with Jensen s reagent [478]. 

Figure 4.18 Analysis of anions in water using ion-pair liquid chromatography. Column, octadecyl-bonded silica gel, 15 cm x 4.6 mm i.d. eluent, 2 mM tetrabutyl-ammonium hydroxide (pH 5.3) in 3% acetonitrile-water flow rate, 1 ml min- detection, UV200 nm. Peaks 1, Br 2, N03 and3,1. ...

For the non-aqueous titration of weak acids a solvent such as an alcohol or an aprotic, solvent is used that does not compete strongly with the weak acid for proton donation. Typical titrants are lithium methoxide in methanol or tetrabutyl ammonium hydroxide in dimethylformamide. End-point detection may be carried out with thymol blue as an indicator or potentiomctrically (see p. 65). 

A reactor was charged with 1,6-hexanedithiol (1.10 mol), diphenyl carbonate (0.728 mol), and 10wt% tetrabutyl ammonium hydroxide in methanol (0.331 mmol) and then heated for 2 hours at 27 kPa while refluxing at 160°C. After reducing the pressure to 6.7 kPa over 8 hours while distilling off phenol, the pressure was further reduced from 4.0 to 2.0 kPa over 3 hours to distillate off both 1,6-hexanedithiol and phenol and the product isolated. 

The phase transfer catalyzed alkylation reaction of dodecyl phenyl glycidyl ether (DPGE) with hydroxyethyl cellulose (HEC) was studied as a mechanistic model for the general PTC reaction with cellulose ethers. In this way, the most effective phase transfer catalysts and optimum reaction concentrations could be identified. As a model cellulose ether, CELLOSIZE HEC11 was chosen, and the phase transfer catalysts chosen for evaluation were aqueous solutions of choline hydroxide, tetramethyl-, tetrabutyl-, tetrahexyl-, and benzyltrimethylammonium hydroxides. The molar A/HEC ratio (molar ratio of alkali to HEC) used was 0.50, the diluent to HEC (D/HEC) weight ratio was 7.4, and the reaction diluent was aqueous /-butyl alcohol. Because some of the quaternary ammonium hydroxide charges would be accompanied by large additions of water, the initial water content of the diluent was adjusted so that the final diluent composition would be about 14.4% water in /-butyl alcohol. The results of these experiments are summarized in Table 2. 

Hydroxymethyl polystyrene has been prepared from chloromethyl polystyrene, either by conversion into the acetate by nucleophilic substitution followed by saponification, or directly by treatment with a mixture of potassium acetate and tetrabutyl-ammonium hydroxide in 1,2-dichlorobenzene/water (85 °C, 2 d [61]). 

Ion-pair chromatography has also been used for the separation of aspartame from other sweeteners. The ion-pair reagents commonly used are triethylammonium phosphate (32), tetra-ethylammonium hydroxyde (47), tetrapropylammonium hydroxide (40), pentanesulfonate (52), tetrabutylammonium phosphate (34), tetrabutylammonium hydrogen sulfate (66), and tetrabutyl-ammonium p-toluenesulfonate (24). 

Figure 7.12 Separation of three compounds using tetrabutylammonium hydroxide in the mobile phase. Elution order (1) permethrin, (2) zidovudine, (3) trimethoprim. Flow = 2 ml/min C02, 100 /d methanol-tetrabutyl-ammonium hydroxide for 2.0 min, 100-500 /d/min methanol-tetrabutyl-ammonium hydroxide for 2.0 min, 100-500 fd/min methanoI-TBAOH in 4.0 min, hold at 500 /d/min. Column Deltabond CN (250 x 4.6 mm ID). Oven temperature 60°C UV detection at 254 nm. (Reprinted from Ref. 9 with kind permission of Dr. Alfred Huthig Verlag GmbH, Heidelberg.)...

LiChrosorb RP-8 (7 pm) 50 mM-KH2P04 with 4 mM-tetrabutyl-ammonium hydroxide at pH 6.5 (1 mL/min) 260 nm Quantitative determination of EDTA and its behavior in radioactive waste solutions. [61]... 

Alkylation of (4) with ethyl bromo acetate was effected under phase-transfer conditions with powdered potassium hydroxide and tetrabutyl ammonium bromide in tetrahydrofuran to yield compound (5), and the azide function in (5) was then reduced by catalytic hydrogenation (over Pd/C) to give (6). The aminoester (6) was resolved into its enantiomers via... 

N-Alkylation of 1,2,3-triazoles and benzotriazoles is readily achieved using (1) alkyl halides, dialkyl sulfates, diazoalkanes, and jS-tosylates or (2) the Mannich reaction. When alkyl halides are used, sodium alkoxide, sodium hydride, or sodium hydroxide is usually employed as the base. The N-alkylation of benzotriazole with alkyl halides proceeds efficiently using powdered NaOH as the base in DMF. The highest yields (80100%) of the alkylated benzotriazoles are obtained when a fourfold excess of NaOFl is employed. A-Alkylbenzotriazoles have been prepared from benzotriazole and alkyl halides using phase-transfer catalysts, e.g., KOFI, benzene, tetrabutyl-ammonium salts or KOH, benzene, polyethylene glycol. 

The commercially available, supported amino acid 1.49 was elaborated to complex linear intermediates that can easily be cyclatively cleaved to produce tetramic acids the cleavage conditions included aqueous NaOEt (107), tetrabutyl ammonium hydroxide (108), and methanolic KOH (109). The procedures afforded the desired heterocycles in good yields and purities. 

Nucleophilic substitution of the iminium ions formed in the electrochemical process provides a convenient route for the synthesis of a-substituted amino derivatives. For example the anodic oxidation of Af,Af-dimethylbenzylamine in methanol containing tetrabutyl ammonium fluoroborate or potassium hydroxide gives rise to methoxylated products (Scheme 39) [261]. 

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