Sodium alcoholate

Under alkaline conditions, an amine addition reaction can occur. For example, in the reaction of C3H3CH2CH2NH2 and aEyl alcohol in the presence of sodium alcoholate at 108°C for 80 h, 43.4% A/-(3-hydroxypropyl)phenylethylamine is formed (12). 

Transesterification, an equiUbrium reaction, is practical only when the alcohol to be esterified has a high boiling point and the leaving alcohol can be removed by distillation. The most widely used catalysts are sodium alcoholates and organic titanates, although amines are also used (30,31). 

The most versatile method of preparing ethers is the Williamson ether synthesis, particularly in the preparation of unsymmetrical alkyl ethers (12,13). The reaction of sodium alcoholates with halogen derivatives of hydrocarbons gives the ethers ... 

Of somewhat greater technical interest are the addition compounds and the cellulose esters and ethers. Of the apparent addition compounds the most important is alkali cellulose produced by steeping cellulose in caustic soda and considered to be of general form (CgHioOs), (NaOH) ) rather than a sodium alcoholate compound. Alkali cellulose is a particularly important starting point in the manufacture of cellulose ethers. The ability of aqueous cuprammonium hydroxide solutions to dissolve cellulose appears to be dependent on addition compound formation. 

A remarkable feature of the Birch reduction of estradiol 3-methyl ether derivatives, as well as of other metal-ammonia reductions, is the extreme rapidity of reaction. Sodium and -butyl alcohol, a metal-alcohol combination having a comparatively slow rate of reduction, effects the reduction of estradiol 3-methyl ether to the extent of 96% in 5 minutes at —33° lithium also effects complete reduction under the same conditions as is to be expected. Shorter reaction times were not studied. At —70°, reduction with sodium occurs to the extent of 56 % in 5 minutes, although reduction with lithium is virtually complete (96%) in the same time. (The slow rates of reduction of compounds of the 5-methoxytetralin type is exemplified by 5-methoxy-tetralin itself with sodium and f-butyl alcohol reduction occurs to the extent of only 50% in 6 hours vs. 99+% with lithium.) The iron catalyzed reaction of sodium with alcohols must be very fast since it competes so well with the rapid Birch reduction. One cannot compensate for the presence of iron in a Birch reduction mixture containing sodium by adding additional metal to extend the reaction time. The iron catalyzed sodium-alcohol reaction is sufficiently rapid that the aromatic steroid still remains largely unreduced. 

The stereochemistry of the product resulting from the reaction of a 17-keto steroid with ethylidenetriphenylphosphorane is different from that of the 17-ethylidene steroids obtained by dehydration of 17a-ethyl-17/ -hydroxy compounds, Wolff-Kishner reduction of A -20-keto steroids or by sodium-alcohol or sodium-ammonia " reductions of 17-ethynyl carbinols. These latter products have generally been assumed to possess the trans configuration (C-21 methyl away from the bulk of the ring system) because of anticipated greater stability. The cis configuration for... 

Ethylmalonic Acid.—Like acetoacetic ester (see p. 83), diethylmalonate contains the gioup CO.CHj.CO. By the action of sodium or sodium alroholate, the hydrogen atoms of the methylene group are successively replaceable by sodium. The sodium atoms are in turn replaceable by alkyl or acyl groups. Thus, in the present preparation, ethyl malonic ester is obtained by the action of ethyl iodide on the monosodium compound. If this substance be treated with a second molecule of sodium alcoholate and a second molecule of alkyl iodide, a second radical would be in roduced, and a compound formed of the general formula... 

These compounds yield, on hydrolysis, the free acids, which, like all acids containing two carbo.xyl groups attached to the same carbon atom, lose COj on heating. Thus, ethyl malonic acid yields butyric acid. In this way the synthesis of monobasic acids may be readily effected. Malonic ester, moreover, may be used in the preparation of cyclic compounds as well as of tetrabasic and also dibasic acids of the malonic acid series ( Perkin). To give one illustration malonic ester, and ethylene bromide in presence of sodium alcoholate, yield triniethyleiic dicarbo.xylic ester and tetramethylene tetracarbo.xylic ester. The first reaction takes place in two steps,... 

The cleavage of isoxazoles with no substituent in the 3-position by sodium alcoholates has been used analytically to determine the percentage of 5-alkyI- and 5-aryl-isoxazoles in mixtures with their 3-isomers (see, e.g., footnotes 19 and 20). 

As stated above it yields dihydromjTcene (dihydro-ocimene) when reduced by sodium alcohol. On hydration by means of acetic and sulphuric acids it yields an alcohol, ocimenol, which has the following characters —... 

By reducing selinene with sodium alcohol, tetrahydroselinene was... 

By heating geranyl chloride with sodium alcoholate geranyl ethyl ethOr was obtained. This body, 10 17 - - CI2H5, is an oil with a faint rose odour, having the following characters —... 

The a.a-diethylacetoacetamide used as starting material was obtained by converting diketene with aqueous ammonia to acetoacetamide and alkylating twice with ethyl bromide in the presence of sodium alcoholate. 

Bellacane Elixir—atropine, scopolamine HBr, hyoseyamine HBr or sulfate, phenobarbital, alcohol, tartrazine Bellacane SR Tablets—1-alkaloids of belladonna, phenobarbital, ergotamine tartrate Bellergal-S Tablets—1-alkaloids of belladonna, phenobarbital, ergotamine tartrate Butibel Elixir—belladonna extract, butabarbital sodium, alcohol, sucrose, saccharin Butibel Tablets—belladonna extract, butabarbitol Chardonna-2 Tablets—belladonna extract, phenobarbital Donnatal Elixir—atropine, scopolamine HBr, hyoseyamine HBr or sulfate, phenobarbital, alcohol, sucrose, saccharin... 

Rawlings and Lingafelter [69] studied the hydrated phases of sodium alcohol sulfates ranging from C6 to C20 and their crystal structures by X rays. The a phase is almost identical to that of the alkylsulfonates but all other phases are different. The crystals of all phases are monoclinic. This work was completed by Prins and Prins [70] who gave more precise details of the polymorphism of sodium alcohol sulfates. 

It can be seen that the solubility in water of sodium dodecyl sulfate is around 30%. However, the triethanolamine salt is still more soluble and forms clear solutions at 40% concentration. Figure 3 shows plots of the solubility of sodium alcohol sulfates with alkyl chains from Cn to C18 vs. temperature. As expected, the solubility decreases as the number of carbon atoms in the alkyl chain increases [80]. 

Dreger et al. [72] reported numerical values for the solubility of several primary and secondary sodium alcohol sulfates at different temperatures. Some of their results are shown in Table 4. 

FIG. 2 Solubility of potassium dodecyl sulfate and sodium alcohol sulfates vs. temperature [68]. 

The Krafft temperature for a homologous series rises as the chain length increases but with independent and different curves for even or odd members [80]. Figure 7 shows the Krafft temperatures of sodium alcohol sulfates ranging from 11 to 18 carbon atoms where the two different curves for odd- and even-numbered series and the alternancy of values can be clearly observed. Lange and Schwuger explain this effect as caused by the different crystal structures of the even and odd numbers. 

TABLE 7 Krafft Temperatures of Sodium Alcohol and Alcohol Ether Sulfates... 

Evans studied the influence of the position of the sulfate group on the CMC at 40°C for a large number of sodium alcohol sulfates [92]. The results are given in Table 10. From these results it is possible to determine the constants A and B of Eq. (11) at 40°C as shown in Table 11. Observation shows a slight constant decrease of the slope (B) of the lines as the sulfate group is shifted toward the middle of the chain whereas the values of A are almost constant for all homologous series. 

TABLE 10 Effect of Position of Sulfate Group on the CMC at 40 °C for Different Sodium Alcohol Sulfates... 

TABLE 11 Constants A and B of Sodium Alcohol Sulfates for Various Positions of the Sulfate Group at 40°C... 

CMC varies with temperature following a polynomial equation. A general equation relating the CMC of sodium alcohol sulfates to the number of carbon atoms in the alkyl chain and temperature (°C) has been suggested [93] ... 

Table 17 shows the CMCs of sodium alcohol propoxysulfates at 20°C determined from surface tension measurements by the maximum bubble pressure [127] and Table 18 shows the critical micelle concentrations of sodium pro-poxylated octylphenol and propoxylated nonylphenol sulfates. Surface tension... 

TABLE 17 CMC (mM) of Different Sodium Alcohol Propoxy Sulfates... 

The adsorption behavior of homologous sodium alcohol sulfates at the interface can be characterized by the adsorption isotherms. However, the adsorption parameters of these isotherms are very sensitive to impurities present in the surfactant. Wiinstneck et al. [145] determined the equilibrium values of... 

Sodium alcohol sulfates have a limited solubility compared to sodium alcohol ether sulfates and are more suitable for cream, pearlized, and paste shampoos. Alcohol sulfates are more frequently used in general shampoo formulations in the United States than in Europe. Europe has moved toward alcohol ether sulfates for historical and traditional reasons, different availability of ethylene oxide, and possibly other technical reasons such as the more favorable dermatological properties of alcohol ether sulfates and their better behavior in hard waters. Triethanolamine alcohol sulfates are widely used in shampoos because of their comparatively high solubility in water, good foaming properties, and low irritancy. 

An important application of some sodium alcohol sulfates, particularly those based on C12 and C12-CI4 and produced in powder and needle forms, is as the basic surfactant ingredient in toothpastes. Sodium and triethanolamine lauryl sulfates are also components of shaving creams. 

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