Ethyl potassium malonate

CI2IK 14459-64-4) see Amidotrizoic acid lodamide potassium ethyl malonate... 

A 250-ml. three-necked flask provided with a stirrer, a dropping funnel, and a thermometer is charged with 80 g. (0.470 mole) of potassium ethyl malonate and 50 ml. of water. The mixture is cooled to 5° with an ice bath, and 40 ml. of concentrated hydrochloric acid is added over a 30-minute period while the temperature is maintained below 10°. The mixture is filtered with suction, and the precipitate of potassium chloride washed with 75 ml. of ether. The aqueous layer of the filtrate is separated and washed with three 50-ml. portions of ether. The com-... 

Potassium 4-chloro-3,5-dinitrobenzene-sulfonate, 31, 46 Potassium cyanate, 31, 9 Potassium cyanide, 30,84 32,31,63 37,47 Potassium ethyl malonate, 37, 34 Potassium ethyl xanthate, 30, 56 Potassium fluoride, 36, 40 Potassium iodide, 30, 34 31, 31, 66 Potassium metal, 37, 29, 30 Potassium methyl sulfate, 31, 73 Potassium nitrate, 31, 46 Potassium 1-nitropropylnitronate, 37, 24 Potassium oxalate, 34, 83 Potassium permanganate, 30, 87 31, 59 Potassium sulfide, 32, 103 Potassium thiobenzoate, 32, 101 Potassium thiocyanate, 32, 39, 40 Prins reaction, 33, 72 Propane, 1, 3-dibromo-2, 2-Ws-(bromo-methyl)-, 31, 82... 

Catalysis by metal ions has also been demonstrated in the hydrolysis of esters containing an a- or /I-carboxylate ion. The alkaline hydrolysis of potassium ethyl oxalate and potassium ethyl malonate is catalyzed by calcium, barium, hexaamino-cobalt(III), and thallous ion, in that order (22). The oxalate ester is catalyzed to a greater extent than the malonate ester, which in turn is more susceptible to catalysis by metal ion than the corresponding adipate ester. Alkali metal ions, on... 

FuranonesS The first step in a simplified synthesis of bislactones involves condensation of an a-halo aldehyde (1) and potassium ethyl malonate (2) in benzene- water in the presence of tetra-n-butylammonium bromide. The furanone 3 is converted to the hislactone 4 by bromination followed by treatment with HBr. The product is a precursor to df-avcnaciolide (5), a fungicide from Aspergillus arenaceous. 

The method of von Miller/3 electrolyzing potassium ethyl--malonate with potassium salts 0 aliphatic carboxylic acids, also gives satisfactory results. If potassium acetate is chosen as the second component of the electrolytic mixture, propionic ethyl ester is formed and likewise by using potassium propionate or potassium butyrate we obtain butyric ethyl ester or valeric ethyl ester respectively. 

Partial saponification of malonic ester occurs with cold alcoholic potassium hydroxide to give potassium ethyl malonate in 82% yield. Esters of dibasic acids having the carboxyl groups farther apart are cleaved in a similar manner under these conditions, e.g., the preparation of the halfester of a-methylpimelic acid (59%)- ... 

Potassium ethyl malonate, 37, 34 Potassium ethyl xanthate, 30, 56 Potassium fluoride, 36, 40 Potassium hypochlorite, 38, 32 Potassium iodide, 30, 34 31, 31, 66... 

The rates of alkaline hydrolysis of the half-esters, potassium ethyl oxalate, malonate, adipate, and sebacate were studied in the presence of potassium, sodium, lithium. thallium(I), calcium(II), barium(II), and hexamminecobalt(III) ions (106). On the basis of the results obtained, chelate formation between the metal ions and the transition state of the substrate was postulated. In these chelate structures (structures XXXVIII), formally similar to those postulated in the hydrolysis of a-amino esters (26), the metal ion facilitates the attack by the hydroxide ion by positioning it in a suitable manner. The rate of hydrolysis of the oxalate half-ester is greater than that of the malonate, which in turn is greater than that of the adipate. This is in the expected order of the stability of the metal chelates. The order for the rate of hydrolysis of the ethyl oxalate and ethyl malonate is Ca2+ Ba2+ > [Co(NH3)6]3+ > T1+. The hexamminecobalt(III) ion seems to be less effective than expected, since it is too large to satisfy the steric requirements of the chelate structures. The alkali metals were found to have marked negative specific salt effects on the rates of reaction of the adipate and sebacate, but only a small negative salt effect on the hydrolysis of potassium ethyl malonate. 

The magnesium etiolate is prepared from 2.1 equivalents of potassium ethyl malonate (16) by treatment w ith 2.0 equivalents of alkyl Grignard (usually methyl or ethyl since these are commercially available). The resulting dianion, shown in Scheme 6.4 as 17. has strong nuclcophilicity at the carbon. 

In accordance with a similar principle they obtained ethyl alcohol from potassium acetate and potassium glycolate. If potassium-ethyl malonate was taken as one of the salts and a solution of this with potassium acetate, propionate, or butyrate was electrolyzed there was formed the ethyl ester of propionic, butyric, or valeric acid, respectively. 

Ethyl-potassium ethyl-malonate gave the corre-... 

Cul in the presence of TMSCl at low temperatures. Saponification provided acid, which was transformed to ketoester 7 by first preparing the acyl imidazolide, followed by treatment with potassium ethyl malonate and MgCl2. 

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