Alkyl sulfates formation

Mono- and dialkyl derivatives can also be prepared using alkyl sulfates. Aryl chlorides are usually inert, unless activated by an electron-withdrawing group. Conversion to alkoxides allows formation of ethers. 

The reaction of alkyl sulfates with alkoxide ions is quite similar to 10-12 in mechanism and scope. Other inorganic esters can also be used. One of the most common usages of the reaction is the formation of methyl ethers of alcohols and phenols by treatment of alkoxides or aroxides with methyl sulfate. The alcohol or phenol can be methylated directly, by treatment with dimethyl sulfate and alumina in cyclohexane. Carboxylic esters sometimes give ethers when treated with alkoxides (Bal2 mechanism, p. 473) in a very similar process (see also 10-24). 

Cosmetic Rinse off Preparations. In certain cosmetic products, tor example hair shampoos, it is not possible to use complexing agents because of the irritation of mucous membranes. Here a low sensitivity of surfactants to water hardness is a precondition for their application. Foam formation is generally considered to be a measure of shampoo quality (Table V). With increase in water hardness the foam volume of alkyl sulfates decreases very much, whereas with the corresponding alkyl ether sulfates this decrease is relatively small. For cosmetic applications, the good skin compatibility and low irritation to mucous membranes of alkyl ether sulfates is of high importance (37). 

Another possibility of transforming indirectly alcohols into alkyllithium compounds consists in nsing the corresponding sulfates. Alkyl sulfates 60 were lithiated using naphthalene (4%) as the electron carrier catalyst in THF at —78 °C yielding two equivalents of the corresponding alkyllithinm 61. Further addition of an electrophile at —78 to 0°C led to the formation, after hydrolysis, of the final prodncts 20 (Scheme 22) ... 

The composition data obtained for the series of mixed fatty acid-potassium soap systems, prepared by both the ethanol and petroleum ether routes, lend strong support to the formation of 1 to 1 acid-soap complexes. It is of interest to inquire into the phase relationships in these two-component systems. A phase diagram presented by McBain and Field (15) for the lauric acid-potassium laurate system shows that compound formation takes place between the two components at the 1 to 1 molar ratio, but the compound undergoes melting with decomposition at 91.3 °C. [A similar type of phase behavior has been reported by us for the sodium alkyl sulfate-alkyl alcohol (9) and sodium alkyl sulfonate-alkyl alcohol (12) systems, but in these cases the stoichiometry is 2 to 1]. 

A better method for studying the alkali metal cation-soap anion interaction on the surface, according to Weil (58), is to assume a similarity between surface behavior and solution behavior and to use the activity coefficient of the solute in the solution as the parameter to account for surface behavior. By plotting activity coefficients as a function of the molality for the salts of the alkali metals (7, 26), the resulting order of the curves of the weak acids (formates, acetates, hydroxides) is the reverse of that found for the strong acids (chlorides, bromides, nitrates, chlorates, sulfates). The activity curves of the acetate salts can be used as the counterparts for the long-chain fatty acid salts, while those for the chlorides can be the analogs of the alkyl sulfates. The scheme is speculative in that the fatty acid and alkyl sulfate salts micellize, and acetate and chloride do not. 

PELOUZE SYNTHESIS. Formation of nitriles from alkali cyanides by alkylation with alkyl sulfates of alkyl phosphates. 

H3PW12O40 shows a higher activity for the alcoholysis of epoxides [Eq. (15)] than H2SO4, PTS, or HCIO4 (9, 124, 175). While rapid deactivation is observed with H2S04, which is probably due to the formation of an alkyl sulfate, H3PW12O40 maintains its high catalytic activity. 

In cases of extensive branching, as for the alkylbenzenesulfonates, the CnH2n+2 1°33 series is significantly perturbed compared to the straight chain alkyl sulfates, but it is sufficiently abundant to show perturbations in the loss pattern. These perturbations may be interpretable for identifying branch points. N-Acylated amino acids also show a suppressed remote charge site loss series because the preferred fragmentations are the decarboxylation of the parent anion and formation of the carboxylate anion of the amino acid (8). 

The effect of increasing the hydrocarbon chain length from methyl to octadecyl on the acid catalyzed, neutral, and base catalyzed hydrolysis of n-alkyl sulfate esters has been examined (Kurz, 1962). The rate constants for the neutral hydrolysis decrease smoothly from methyl to dodecyl sulfate and hence are unaffected by micellization of the longer chain esters. The rate constants for the acid-catalyzed hydrolysis, however, are relatively constant for the non-micellar ester but increase dramatically with micelle formation (Table 7). Conversely, the hydroxide... 

Butyl sulfate formation Is the primary Intermediate to alkylate when n-butenes are used with sulfuric acid at temperatures up to at least 0°C (6). Butyl fluorides are also produced at low temperatures with HF (23). 

Recent Purdue results (5) have now shown at -10°C or less and in the presence of relatively little excess sulfuric acid that n-butenes both isomerize and form sec-butyl sulfate, see Reaction I-l. It seems safe to conclude that significant amounts of sulfate formation also occur in commercial alkylation reactors operated at about 5 to 15 C. The evidence supporting the formation of sulfates is as follows ... 

The acid charge to the absorber is the used sulfuric acid catalyst from the alkylation settler. It usually is of about 90% titratable acidity with about 3-5% water and 3-6% conjunct polymer. The alkylation catalyst is no longer active as an alkylation catalyst when the acidity drops to about 80% due to the pick up of conjunct polymer and alkyl sulfates. However, it is still active for the absorption of propylene until substantially all of the acid is converted to alkyl sulfates. Since the formation of alkyl sulfates from olefins and sulfuric acid are equilibrium reactions, conditions should be used which will shift the equilibrium to the right, or to the dialkyl sulfate, with minimum formation of alkyl acid sulfate. 

The alkynide ion can undergo alkylation with a variety of alkylating reagents, such as haloalkanes and alkyl sulfates, with the formation of a carbon-carbon bond. The alkynide ion is also strongly basic so that elimination reactions may accompany or subvert the substitution reaction. Group I metal alkynides in liquid ammonia give mainly substitution products with primary haloalkanes but secondary and tertiary haloalkanes give mainly elimination products, as do 2-substituted primary haloalkanes (equation 1). 

Schwuger [4] has investigated the effects of ether groups on the solubility, surface properties, and detergency of alkyl ether sulfates. Addition of ethylene oxide groups to the alkyl surfactants increases solubility, thus reducing the formation of precipitates and maintaining foam volume in the presence of Ca2+ and Mg2+ ions. The use of ether sulfates would be preferred over that of alkyl sulfates for a clear formulation. 

Alkylation of pyrimidinethiones is on the sulfur atom (Scheme 75). Alkyl halides, sulfonates, or sulfates effect the reaction in the presence of a base under mild conditions [Pg.187]

Cations can be formed from alcohols, and they add to aromatic rings in the usual manner. Sulfuric acid is a common catalyst for alcohols, forming an alkyl sulfate that then reacts with the aromatic substrate. 120 Alcohols are more reactive than halides, although large quantities of the Lewis acid are usually required for Friedel-Crafts reactions.I2l Alcohols form a complex with aluminum chlorides [R(H)0— A1C13], and a complicating side reaction is loss of HCl and formation of an alkyl chloride.122 a full equivalent of the Lewis acid... 

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