Sodium carboxylates with

Scheme 5.8 Formation of sodium carboxylates with 2-dialkyl-imidazolium-carboxylate as the C02-carrier [40].

Diorgano tellurium dichlorides and dibromides react with silver carboxylates " " or sodium carboxylates with formation of diorgano tellurium dicarboxylates. The same conversion was accomplished by shaking diaryl tellurium dichlorides with an Amberlite IR 45 resin in the carboxylate form or by treating bis[trifluoromethyl] tellurium dihalides with trifluoroacetic anhydride. ... 

Table 8 Acid Anhydrides from the Reaction of Sodium Carboxylates with Acyl Chlorides...

Mean while, to a mixture of 190.0 g 2-bromo-4-fluoro-aniline (1 mol) and 0.6 L water at room temperature was added 3 mol concentrated HCI the resulting thick white slurry was cooled to 0°C. A solution of 1 mol NaN02 in 0.7 L water was added slowly over 25 min, at such a rate as not to exceed an internal temperature of 10°C, and the reaction was aged for 30 min before filtration to remove any insoluble precipitate. This filtered diazonium solution was added to the prepared sodium carboxylate solution at 0°C dropwise over a period of 40 min (Note If added to the solution of sodium carboxylate, then it was not necessary to acidify the sodium carboxylate with concentrated HCI.) The resulting thick yellow slurry was stirred to room temperature, filtered, and dried under a stream of nitrogen to give 270.9 g (4 1 ratio) l-( /Z)-cyclopentane-l,2-dione (2-bromo-4-fluorophenyl)hydrazone as a yellow solid, in a yield of 95%, m.p. 182-187°C. 

This methodology was also applied to the crossed Claisen reaction between carboxylic acids and methyl hexanoate. The carboxylic acids are initially converted to mixed anhydrides by reacting their in situ formed sodium carboxylates with chlorofor-mates these intermediates then react with NMI as shown previously to form electrophilic acyl ammonium species (eq 46). This strategy was applied to the synthesis of natural perfumes such as (/ )-muscone and cw-jasmone. ... 

Yu et al. in 2008 pioneered the palladium(II)-catalyzed carbonylation of aromatic or vinyl acid for the preparation of 1,2- and 1,3-dicarboxylic acid under 1 atm of CO (Table 15.13) [18]. Treatment of sodium carboxylate with Pd(OAc)2 in CH2CI2 or dioxane at 100 °C formed a C-H insertion intermediate complex. A suspension of this palladacycle in solvent could react stoichiometrically with CO under room temperature producing the anhydride acid quantitatively which was finally hydrolyzed to dicarboxylic acid in situ under the base and trace amount of water. Twenty-four examples were prepared and isolated through this protocol. 

Detergents are designed to be effective in hard water meaning water containing calcium salts that form insoluble calcium carboxylates with soaps These precipitates rob the soap of Its cleansing power and form an unpleasant scum The calcium salts of synthetic deter gents such as sodium lauryl sulfate however are soluble and retain their micelle forming ability even m hard water... 

These equations tell us that the reverse process proton transfer from acids to bicarbon ate to form carbon dioxide will be favorable when of the acid exceeds 4 3 X 10 (pK, < 6 4) Among compounds containing carbon hydrogen and oxygen only car boxylic acids are acidic enough to meet this requirement They dissolve m aqueous sodium bicarbonate with the evolution of carbon dioxide This behavior is the basis of a qualitative test for carboxylic acids... 

Monohydroxyaluminum distearate, (HO)Al(OOC(CH2) gCH2)2, used to be the largest selling aluminum carboxylate (1). Although stiU sold, the product is no longer Hsted in the U.S. International Trade Commission Report (1) because of low volume or confidentiahty constraints because of too few supphers. Aluminum distearate is a white powder that is insoluble in water, alcohol, and ether. A key property is its abiUty to gel vegetable oils and hydrocarbons. Aluminum distearate is prepared by the reaction of aqueous sodium stearate with aqueous aluminum sulfate or chloride at pH 7.3. Aluminum monostearate is formed if the sodium stearate solution is held at pH 9.5 (44). 

The anti-inflammatory agent Oxapro2in, 2-(4,5-diphenyl-2-oxa2ole)propionic acid mono aluminum and dihydroxyalurninum salts, is made by reaction of the sodium salt with aluminum sulfate under controlled conditions (96). Again, the aluminum salts of many carboxylic acid based dmgs are less irritating, ulcerous, and/or toxic, and have a more pleasant taste than their parent acids. 

In addition to their work on naphthocoumarins, Sen and Kakaji showed that 4-t-butyl-2-hydroxyphenones 50 gave exclusively coumarins 51 when treated with various anhydrides in the presence of their corresponding sodium carboxylates. They saw similar results with 4-t-amyl-2-hydroxyphenones. 

If the hydroxy-acid is heated with hydrobromic acid, it is converted into l-methyl-l-bromocyclohexane-4-carboxylic acid, and this is decomposed by boiling with sodium carbonate with loss of hydrogen bromide and with formation of 1-methyl-A cyclohexene-4-carboxyhc acid—... 

Preparation of 7-(D-0t-phenyigiycyiamido)-3-chioro-3-cephem-4-carboxyiic acid To a suspension of 280 mg (1.2 mmol) of 7-amino-3-chloro-3-cephem-4-carboxylic acid in 14 ml of acetonitrile was added with stirring at room temperature 0.5 ml of N, 0-bis-(trimethylsilyl)acetamide to form the soluble disilylmethyl derivative thereof. The solution was cooled to 0°C and was slowly added to a solution of the mixed anhydride formed by reacting 408 mg (1.5 mmol) of methyl-3-a-carboxybenzylaminocrotonate sodium salt with 161 mg (1.7 mmol) of methyl chloroformate in the presence to 2 drops of N, N-dimethylbenzyl amine in 7 ml of acetonitrile. 

Cysteine is first dissolved in distilled water which has been freed of oxygen by boiling. Formaldehyde of 30% (w/v) concentration is added while stirring and the temperature of the mixture rises, while the thiazolidine carboxylic acid begins crystallizing. The stirring is continued for 2 hours after which ethyl alcohol of 95% (w/v) concentration Is added to induce further crystallization. The mixture is left to stand for 24 hours at 4°C. The mixture is then filtered with retention of a crude product, which is purified by recrystallization from boiling distilled water. The crystals are then dried at about 40°C. The free acid is then converted to the sodium salt with NaOH. 

The solution is allowed to stand in a separatory funnel for at least 30 min before the aqueous layer is drained out. It is sometimes observed that a portion of the sodium carboxylate salt of 4 forms a third layer below the aqueous layer, in which case this layer should be combined with the sodium carbonate... 

A dissertation from 1943 [2] describes an interesting investigation concerning synthesis and properties of pure ether carboxylates. With metallic sodium and chloroacetic acid ethyl ester followed by saponification, ether carboxylates were made with the general formula... 

Already in 1943 M. Schuler [2] described the comparison of the surface-active properties of sodium palmitate with several ether carboxylates based on a constant amount of C atoms. The results showed that with more O bridges the optimal surface activity and emulsifying properties can be achieved at lower temperature, with the detergent properties decreasing and solubility increasing. 

Comparison of C12-C14 polyether carboxylates with 3, 4, and 5 mol EO with sodium lauryl ether sulfate (2 mol EO) indicated approximately the same detergency and a little better wetting using the ether carboxylates, with the remark that 4 EO gave the optimum [10]. 

In 1973 it was published that in contrast to lauryl ether sulfate the lauryl ether carboxylic acid sodium salt with 3 mol EO did not disturb the skin s water loss and did not decrease the skin s resistance [74], Formulation tests for the use as emulsifier in creams were described in 1976 [75]. 

In combination with alkyl ether sulfates, a synergistic decrease of the irritation level of the ether sulfates and an improvement of the foam stabilization has been described [57,67,78]. A good compromise between mildness and foam properties could be achieved with lauryl ether carboxylic acid sodium salt with 10 mol EO [57,67]. In several articles examples of the use of alkyl ether carboxylates as cosurfactant in mild shampoos as well as bath and shower products have been described [57,69,79]. 

For example, the LD50 value of sodium lauryl ether carboxylate with 4.5 mol EO is about 3-4 g/kg [51,57] and of sodium myristyl ether carboxylate with 3.5 mol EO about 4 g/kg [57]. 

The synthesis of chaparrinone and other quassinoids (naturally occurring substances with antileukemic activity) is another striking example [16a-c]. The key step of synthesis was the Diels-Alder reaction between the a,/l-unsaturated ketoaldehyde 1 (Scheme 6.1) with ethyl 4-methyl-3,5-hexadienoate 2 (R = Et). In benzene, the exo adduct is prevalent but it does not have the desired stereochemistry at C-14. In water, the reaction rate nearly doubles and both the reaction yield and the endo adduct increase considerably. By using the diene acid 2 (R = H) the reaction in water is 10 times faster than in organic solvent and the diastereoselectivity and the yield are satisfactory. The best result was obtained with diene sodium carboxylate 2 (R = Na) when the reaction is conducted 2m in diene the reaction is complete in 5h and the endo adduct is 75% of the diaster-eoisomeric reaction mixture. 

Foreign cations can increasingly lower the yield in the order Fe, Co " < Ca " < Mn < Pb " [22]. This is possibly due to the formation of oxide layers at the anode [42], Alkali and alkaline earth metal ions, alkylammonium ions and also zinc or nickel cations do not effect the Kolbe reaction [40] and are therefore the counterions of choice in preparative applications. Methanol is the best suited solvent for Kolbe electrolysis [7, 43]. Its oxidation is extensively inhibited by the formation of the carboxylate layer. The following electrolytes with methanol as solvent have been used MeOH-sodium carboxylate [44], MeOH—MeONa [45, 46], MeOH—NaOH [47], MeOH—EtsN-pyridine [48]. The yield of the Kolbe dimer decreases in media that contain more than 4% water. 

A mixture of water/pyridine appears to be the solvent of choice to aid carbenium ion formation [246]. In the Hofer-Moest reaction the formation of alcohols is optimized by adding alkali bicarbonates, sulfates [39] or perchlorates. In methanol solution the presence of a small amount of sodium perchlorate shifts the decarboxylation totally to the carbenium ion pathway [31]. The structure of the carboxylate can also support non-Kolbe electrolysis. By comparing the products of the electrolysis of different carboxylates with the ionization potentials of the corresponding radicals one can draw the conclusion that alkyl radicals with gas phase ionization potentials smaller than 8 e V should be oxidized to carbenium ions [8 c] in the course of Kolbe electrolysis. This gives some indication in which cases preferential carbenium ion formation or radical dimerization is to be expected. Thus a-alkyl, cycloalkyl [, ... 

Unsymmetrical as well as symmetrical anhydrides are often prepared by the treatment of an acyl halide with a carboxylic acid salt. The compound C0CI2 has been used as a catalyst. If a metallic salt is used, Na , K , or Ag are the most common cations, but more often pyridine or another tertiary amine is added to the free acid and the salt thus formed is treated with the acyl halide. Mixed formic anhydrides are prepared from sodium formate and an aryl halide, by use of a solid-phase copolymer of pyridine-l-oxide. Symmetrical anhydrides can be prepared by reaction of the acyl halide with aqueous NaOH or NaHCOa under phase-transfer conditions, or with sodium bicarbonate with ultrasound. 

The traditional method for transforming carboxylic acids into reactive acylating agents capable of converting alcohols to esters or amines to amides is by formation of the acyl chloride. Molecules devoid of acid-sensitive functional groups can be converted to acyl chlorides with thionyl chloride or phosphorus pentachloride. When milder conditions are necessary, the reaction of the acid or its sodium salt with oxalyl chloride provides the acyl chloride. When a salt is used, the reaction solution remains essentially neutral. 

The acyl azide intermediates are prepared either by reaction of sodium azide with a reactive acylating agent or by diazotization of an acyl hydrazide. An especially convenient version of the former process is treatment of the carboxylic acid with ethyl chloroformate to form a mixed anhydride, which then reacts with azide ion.265... 

Preparation and Reactions of S-b-MM. As mentioned in the introduction, we were interested in block copolymers of styrene and alkali metal methacrylates with overall molecular weights of about 20,000 and methacrylate contents on the order of 10 mol%. The preparation of such copolymers by the usual anionic techniques is not feasible. An alternative is to prepare block copolymers of styrene and methacrylic esters by sequential anionic polymerization, followed by a post-polymerization reaction to produce the desired block copolymers. The obvious first choice of methacrylic esters is methyl methacrylate. It is inexpensive, readily available, and its block copolymers with styrene are well-known. In fact, Brown and White have reported the preparation and hydrolyses of a series of S-b-MM copolymers of varying MM content using p-toluenesulfonic acid (TsOH) (6). The resulting methacrylic acid copolymers were easily converted to their sodium carboxylates by neutralization with sodium hydroxide. 

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