Potassium ethyl succinate

According to the method of Brown and Walker,4 adipic diethyl ester is formed from ethyl potassium succinate ... 

Adipic acid from ethyl-potassium succinate. 

The Brown-Walker 1 method has been found to be of excellent service in the electrolysis of the potassium salts of the mono-esters of malonie acid. The formation of the diethyl ester of succinic acid from ethyl potassium malonate has already been mentioned fp. 103). 

From ethyl potassium, diethylmalomte a substance having the composition Culhr/b, and which differs from the expected tetraethyl-succinic acid by C2II4, was obtained. The nature of this body has not yet teen determined. 

Ethyl-potassium methyl-malonate gave the two symmetrical dimethyl-succinic acids, having the melting-points 193 and 121°. 

Ethyl-potassium dimethyl-malonate gave tetra-methyl-succinic acid. 

Ethyl oxalylsuccinate has been prepared by the condensation of ethyl oxalate with ethyl succinate in the presence of sodium ethoxide or of potassium ethoxide. The method described above is somewhat more convenient, and has given a higher yield of a better product, than one based upon sodium ethoxide, submitted by A. E. Martell and R. M. Herbst. 

The methyl esters of dicarboxylic acids88 give no dicarboxylic products only mono-carboxylic acid derivatives are formed. Dimethyl succinate, dimethyl maleate and dimethyl acetylenedicarboxylate over potassium tetrafluorocobaltate(III) at 270-350"C all give mixtures of (crude products are converted into ethyl esters) ethyl pentafluoropropanoate and ethyl... 

Yon Miller and Hofer 3 have also carried out the principle of the electrolysis of mixtures, discussed under malonic acid, using potassium ethyl succinate, and submitting the latter to electrolysis at the anode with potassium salts of monocarboxylic acids. They thus obtained on the addition of potassium acetate about 69% of the theoretical quantity of butyric ethyl ester ... 

The synthesis of valeric ethyl ester from potassium ethyl succinate and sodium propionate was accomplished in the same way ... 

Furthermore, by using a mixture of potassium ethyl succinate and potassium isobutymlc, isobutylaeet ir ester was ohtaiiiet ... 

The product from Step 2 (1.16 mol), ethyl succinate (1.85 mol), potassium t-butoxide (1.74 mol) and 2.5 L t-butyl alcohol were mixed and a temperature rise to 45 °C observed. Thereafter, the mixture was stirred for 7 hours at ambient temperature and then poured into ice water acidified with HCl to pH 3. The product was extracted with diethyl ether and dried. Overnight the Z isomer precipated from solution, was filtered from the mixture, re-crystallized in isopropanol, and had a mp = 184-186 °C. The corresponding (E) isomer was obtained upon evaporation of the solvent. 

Potassium bitartrate and calcium tartrate are responsible for the physical stability of wines. A portion of tartaric acid slowly esterifies with ethanol to form ethyl bitartrate. Malic acid is converted to lactic acid (0-2.5 g/L) during malolactic fermentation, and the taste of wine becomes weaker. Succinic and acetic acids are also formed during fermentation [18,19]. The content of organic acids in vinegar and wines is shown in Table 10.7. 

In this way they prepared butyric ethyl ester from potassium acetate and potassium-ethyl succinate. The synthesis of the ethyl ester of valeric, capronic, and isobutyl-acetic acid was also effected. 

Potassium ethoxide was prepared from 1.95 g potassium and 9.2 mL absolute ethanol in 150 mL anhydrous ether. To this mixture 14.6 g diethyl oxalate was added. After 15 min, a solution of 13.5 g ethyl (3Lmethoxy-2-biphenylyl)-acetate in 50 mL dry ether was added, and the mixture was refluxed for 51 h. The reaction mixture was cooled and extracted with 5% sodium hydroxide solution. The aqueous layer was saturated with carbon dioxide, and the precipitated oil was taken up in ether. Evaporation of the ether solution afforded 10.6 g crude diethyl Q -keto-Q -(3-methoxy-2-biphenylyl)-succinate, which was used in subsequent experiments without purification. From the alkali-insoluble fraction, 4.2 g ethyl (3 -methoxy-2-biphenylyl)-acetate was recovered. 

The second approach for improving the processabihty of ICPs is to prepare their colloidal dispersions in water or an appropriate solvent The colloid dispersions of ICPs can be obtained by chemical or electrochemical oxidation of the monomer in the presence of a steric stabihzer [29-31].The key parameter for such synthesis is the choice of an appropriate steric stabihzer which adsorbs or grafts onto the polymer coUoidal particles to prevent their aggregation or precipitation. Several polymers such as polyfethylene oxide) [32], poly(vinyl pyrroHdone) [33,34], poly(vinyl alcohol) [35], ethyl hydroxy cellulose [36], poly(vinyl alcohol-co-acetate) [37], poly(vinyl methyl ether) [38,39] and block copolymer stabihzer [40] have been used as steric stabihzers to produce PPy coUoidal dispersions. Surfactants are also employed for the synthesis of ICP coUoidal dispersions [41,42]. Very recently, stable PPy dispersions were prepared by Lu et al. by polymerizing pyrrole in an aqueous medium containing different anionic salts such as sodium benzoate, potassium hydrogen phthalate, and sodium succinate [43]. These authors also reported that the conductivity of PPy dispersions was enhanced when sodium benzoate was used as dopant. Chemical oxidahve polymerization in the presence of PSS in aqueous medium produces coUoidal dispersions and improves processability [44]. CoUoidal dispersions... 

Toluene, tetrahydrofurane, chloroform, 2-(4-hydroxyphen-ylazo)benzoic acid (HABA), potassium trifluoroacetate, aflyl alcohol, succinic anhydride, naphthaline, potassium, and (l-ethyl-3-(3-dimethylaminopropyl)carbodiimid hydrochloride (EDC) were purchased from Sigma-Aldrich, Germany, in highest quality. Diethoxydimethylsilane (D), methyltrimethoxysilane (T), triethoxysilane (T-H) and tetramethyldisiloxane (M-H) were obtained from Wacker Chemie, Germany. Dodecylbenzenesulfonic acid (DBS), p-chloromethylphenyltrimethoxysilane (ClBz-T) and the Karstedt-Catalyst were purchased from ABCR, Germany. 

Brooks states that this substance reacts quantitatively with bisulphite solution, but that it cannot be recovered from the bisulphite compound. This renders it jM-obable that the group CH. CH. CO is present in this body. The fact that the substance is a ketone is proved by its behaviour towards ammoniacal silver solution and magenta solution. The phenyl-hydrazone melts at 161. The ketone does not react with acetanhydride,. and with acetyl chloride it resinifies. When heated with an excess of alcoholic potash solution it gives rise to neutral succinate of potassium. It would seem that the succinic acid occurs in the ketone-molecule in the form of a neutral ester. In order to identify the alcohols which were associated with the succinic acid, the ketone was saponified with aqueous solution of caustic soda, but only ethyl alcohol could be detected. It appears that one of the carboxyl groups of the succinic acid is esterified with ethyl alcohol and the other with an alcohol Ok ijOj. ... 

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