Alkylation, sodium hydroxide Solubility

Notes on the preparation of secondary alkylarylamines. The preparation of -propyl-, ijopropyl- and -butyl-anilines can be conveniently carried out by heating the alkyl bromide with an excess (2-5-4mols) of aniline for 6-12 hours. The tendency for the alkyl halide to yield the corresponding tertiary amine is thus repressed and the product consists almost entirely of the secondary amine and the excess of primary amine combined with the hydrogen bromide liberated in the reaction. The separation of the primary and secondary amines is easily accomplished by the addition of an excess of per cent, zinc chloride solution aniline and its homologues form sparingly soluble additive compounds of the type B ZnCl whereas the alkylanilines do not react with sine chloride in the presence of water. The excess of primary amine can be readily recovered by decomposing the zincichloride with sodium hydroxide solution followed by steam distillation or solvent extraction. The yield of secondary amine is about 70 per cent, of the theoretical. 

Various ether derivatives of cellulose, including some that are water-soluble, are important [Heinz and Liebert, 2001 Just and Majewicz, 1985 Zhang, 2001]. Methyl cellulose and car-boxymethyl cellulose (R = CH3 and CH2COOH, respectively) are synthesized by reaction of cellulose with sodium hydroxide followed by the appropriate alkyl halide ... 

The use of mixtures of sodium hydroxide and benzyltrimethylammonium chloride or tetrabutylammonium bromide failed to enhance the DPGE alkylation of HEC by the in situ formation of the corresponding quaternary ammonium hydroxide phase transfer catalyst. These quaternary ammonium halides are too soluble in aqueous /-butyl alcohol and are preferentially extracted into the organic phase. Mixtures of benzyltrimethylammonium hydroxide and sodium acetate were also ineffective in enhancing the DPGE alkylation of HEC for the same reason, namely preferential solubility of benzyltrimethylammonium acetate in the organic phase. 

Sulfonation of the detergent alkylate gives exclusively the 4-dodecy I benzene-sulfonic acids, which with sodium hydroxide form water-soluble dodecylben-zenesulfonates ... 

Sensitive to oxidation and hydrolysis forms alkylating and carbamoylating intermediates. Half-life of 117 minutes at 25°C and neutral pH.2 Solubility below 0.05 mg/mL in water, 0.1 N sodium hydroxide, 0.1 N hydrochloric acid or 10% ethanol 70 mg/mL in absolute ethanol.1... 

The red, crystalline tellurium bis[0-alkyl dithiocarbonates] are reasonably stable compounds that are insoluble in water, but soluble in chlorinated hydrocarbons and ethanol. Aqueous and ethanolic sodium hydroxide decompose the compounds to tellurium and tellurite3. The tellurium atom is surrounded in these compounds by four sulfur atoms forming a trapezoidal plane with tellurium at the center. The dithiocarbonate groups arc... 

Dialkyl, diaryl, alkyl aryl, and heterocyclic tellurium oxides are known. Most of these compounds are white solids that are soluble in sodium hydroxide. Diorgano tellurium oxides appear to be oxidized by atmospheric oxygen. Their exposure to air should be minimized5. The protonation constant of dimethyl tellurium oxide in water was found to be 6 (pKa)6,7, and of bis[4-methoxyphenyl] tellurium oxide in acetonitrile 14.9s. The barrier to inversion for dihydrogen tellurium oxide (H2Te = 0), the parent compound of diorgano tellurium oxides, was determined as 92.4 kJ/mol (22.0 kcal/mol) by extended Hiickel calculations9. 

Isogai and coworkers [99] recently prepared a series of tri-O-alkylcellulose ethers using a technique that was originally developed for permethylations and involves the use of alkyl halides, powdered sodium hydroxide, and non-aqueous solvents. Water-soluble phosphonomethylcellulose products have been produced by modiflcation of cellulose ethers with chloromethanephos-phonic acid derivatives [87,100]. Low levels of hydrocarbon residues can be incorporated into cellulose ethers, such as hydroxyethylcellulose, to yield high-viscosity, water-soluble products that display non-Newtonian behavior at low shear rates [ 101,102]. Small amounts of 2-(A, yV-diethylamino)ethylcel-lulose can be produced by the Williamson reaction of alkali cellulose with the hydrochloride of 2-chloroethyldiethylamine [103]. 

Aromatic sulfonic acids can be converted to their respective salts by neutralization with an appropriate base. For example, reaction of potassium hydroxide (KOH) with a sulfonic acid produces a potassium sulfonate sodium hydroxide (NaOH) and the sulfonic add produce a sodium sulfonate and ammonium hydroxide (NH4OH) and the aromatic sulfonic acid produce anunonium sulfonate. A wide range of aromatic sulfonic acid salts can be produced from various aliphatic and aromatic amines and metal cations. The neutralization is conveniently done in water, since the sulfonates, and even more so the short alkyl chain hydrotropes, are generally water soluble to the extent of 30-50%. 

Most compounds are soluble in cold, concentrated sulfuric acid, except for inert compounds (alkanes, alkyl halides and aromatic compounds without a functional group). Of the compounds included in this experiment, alcohols, ketones, aldehydes, and esters belong to this category of being soluble in sulfuric acid. These compounds are described as being "neutral." However, it must be mentioned that all of the classes of compounds shown in the Solubility chart, except for the inert compounds, will react with cold, concentrated sulfuric acid—not just the "neutral" compounds, alcohols, ketones, aldehydes, and esters. You must be certain that you have first screened your unknown for solubility in water, sodium bicarbonate, sodium hydroxide, and hydrochloric acid, before trying concentrated sulfuric acid. Inert compounds, which are not included as unknowns, are not soluble in sulfuric acid. Sulfuric acid should always be your last choice of solubility reagents to try. 

Alkyl-aryl ethers are often synthesized by carefully controlling solubility. Both the alkyl halide and phenol are dissolved in dichloromethane then the solution is mixed with an aqueous solution of sodium hydroxide. Phenol, a poor nucleophile, reacts with sodium hydroxide in the aqueous phase to form the phenoxide ion, a good nucleophile. Alkyl-aryl ethers can be synthesized by treating the sodium salt of a phenol with an alkyl halide. The following example illustrates the Williamson synthesis of allyl-aryl ethers. The Bu N+Br is used to facilitate reaction between the polar phenoxide salt and the hydrophobic alkyl halide in the mixed solvent. 

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