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Malonic acid, malonate

The Doebner condensation uses malonic acid, malonic acid monoesters, or cyanoacetic acid instead of the coiTesponding dialkyl malonates. Usually the product stereoisomer with the carboxyl group trans to the larger substituent predominates. [Pg.216]

Blauc s rule Ail dicarboxyiic acids, with the exception of oxalic and malonic acids, up to... [Pg.61]

Carbon suboxide, C3O2, OCCCO. M.p. — 107 C, b.p. 6-8°C. A toxic gas (malonic acid plus P2O5) which polymerizes at room temperature. Reforms malonic acid with water. [Pg.82]

CH OfiSj, H2C(S03H)2- a colourless, crystalline solid which readily absorbs water vapour decomposes on distillation. The potassium salt is prepared by heating methylene chloride with an aqueous solution of potassium sulphite under pressure at 150-I60" C. The free acid is obtained by decomposing the sparingly soluble barium salt with sulphuric acid. The aryl esters are very stable, but the alkyl esters decompose on heating to give ethers. Resembles malonic acid in some of its reactions. [Pg.259]

The BZ reaction involves the oxidation of an organic molecule (citric acid, malonic acid (MA)) by an... [Pg.1100]

The reaction involving chlorite and iodide ions in the presence of malonic acid, the CIMA reaction, is another that supports oscillatory behaviour in a batch system (the chlorite-iodide reaction being a classic clock system the CIMA system also shows reaction-diffusion wave behaviour similar to the BZ reaction, see section A3.14.4). The initial reactants, chlorite and iodide are rapidly consumed, producing CIO2 and I2 which subsequently play the role of reactants . If the system is assembled from these species initially, we have the CDIMA reaction. The chemistry of this oscillator is driven by the following overall processes, with the empirical rate laws as given ... [Pg.1102]

Lengyel I, Rabai G and Epstein I R Experimental and modelling study of oscillations in the chlorine dioxide-iodine-malonic acid reaction J. Am. Chem. See. 112 9104-10... [Pg.1117]

Patel H M, Didymus J M, Wong K K W, Hirsch A, Skiebe A, Lamparth I and Mann S 1996 Fullerates interaction of divalent metal ions with Langmuir monolayers and multilayers in mono-substituted Cgg-malonic acid J. Chem. Soc., Chem. Commun. 611-2... [Pg.2431]

The existence of chaotic oscillations has been documented in a variety of chemical systems. Some of tire earliest observations of chemical chaos have been on biochemical systems like tire peroxidase-oxidase reaction [12] and on tire well known Belousov-Zhabotinskii (BZ) [13] reaction. The BZ reaction is tire Ce-ion-catalyzed oxidation of citric or malonic acid by bromate ion. Early investigations of the BZ reaction used tire teclmiques of dynamical systems tlieory outlined above to document tire existence of chaos in tliis reaction. Apparent chaos in tire BZ reaction was found by Hudson et a] [14] aiid tire data were analysed by Tomita and Tsuda [15] using a return-map metliod. Chaos was confinned in tire BZ reaction carried out in a CSTR by Roux et a] [16, E7] and by Hudson and... [Pg.3060]

Consequently, when D /Dj exceeds the critical value, close to the bifurcation one expects to see the appearance of chemical patterns with characteristic lengtli i= In / k. Beyond the bifurcation point a band of wave numbers is unstable and the nature of the pattern selected (spots, stripes, etc.) depends on the nonlinearity and requires a more detailed analysis. Chemical Turing patterns were observed in the chlorite-iodide-malonic acid (CIMA) system in a gel reactor [M, 59 and 60]. Figure C3.6.12(a) shows an experimental CIMA Turing spot pattern [59]. [Pg.3069]

The crude product is evaporated to dryness and then heated with a mixture of ethanol and sulphuric acid the cyano group is thus hydrolysed giving malonic acid, which then undergoes esterification to give diethyl malonate. [Pg.272]

It follows therefore that ethyl malonate can be used (just as ethyl aceto- acetate) to prepare any mono or di-substituted acetic acid the limitations are identical, namely the substituents must necessarily be alkyl groups (or aryl-alkyl groups such as CjHjCHj), and tri-substituted acetic acids cannot be prepared. Ethyl malonate undergoes no reaction equivalent to the ketonic hydrolysis of ethyl acetoacetate, and the concentration of the alkali used for the hydrolysis is therefore not important. [Pg.276]

Ethane tetracarboxylic ethyl ester can be regarded as composed of two malonic ester residues, each acting as a mono-alkyl substituent to the other. The two remaining hydrogen atoms therefore still retain acidic properties, and consequently the ester gives with sodium ethoxide a di-sodium derivative. [Pg.277]

The term Knoevenagel Condensation was originally applied to the base-catalysed condensation of the carbonyl ( CO) group of aldehydes and ketones with the reactive methylene group of malonic acid, with loss of w ater ... [Pg.279]

It is now applied more widely to include malonic acid derivatives, such as diethyl monoethyl-malonate, ethyl cyanacetate, etc. Various amines may be used as catalysts, and usually the most effective is piperidine (hexahydro-pyridine) a mixture of piperidine and pyridine, or pyridine alone, is also often used. [Pg.279]

The role of the base is apparently primarily that of a proton remover from the reactive methylene group thus if B represents the base, reaction (i) gives the carbanion, which then combines with the positive carbon of the carbonyl group (reaction ii) the product regains a proton from the piperidinium ion, and then by loss of water followed by mono-decarboxylation of the malonic acid residue gives the final acid. [Pg.279]

The reaction is readily illustrated by the formation of crystalline sorbic acid by the condensation of crotonaldehyde and malonic acid in hot pyridine solution ... [Pg.280]

Add 4 g. of malonic acid to 4 ml. of pyridine, and then add 3 1 ml. of crotonaldehyde. Boil the mixture gently under reflux over an asbestos-covered gauze, using a small Bunsen flame, for 40 minutes and then cool it in ice-water. Meanwhile add 2 ml. of concentrated sulphuric acid carefully with shaking to 4 ml. of water, cool the diluted acid, and add it with shaking to the chilled reaction-mixture. Sorbic acid readily crystallises from the solution. Filter the sorbic acid at the pump, wash it with a small quantity of cold water and then recrystallise it from water (ca, 25 ml.). The colourless crystals, m.p. 132-133°, weigh ro-i-2 g. [Pg.280]

Barbituric acid and 2-thiobarbituric acid are readily prepared by the condensation of diethylmalonate with urea and thiourea respectively, in the presence of sodium ethoxide. The use of substituted derivatives of urea and thiourea and of diethyl malonate will clearly lead to a wide range of barbituric and thiobarbituric acids having substituents in the i, 3, or 5 positions. [Pg.306]

Dissolve 13 g. of sodium in 30 ml. of absolute ethanol in a 250 ml. flask carrying a reflux condenser, then add 10 g. (9 5 ml.) of redistilled ethyl malonate, and place the flask on a boiling water-bath. Without delay, add a solution of 5 3 g. of thiourea in a minimum of boiling absolute ethanol (about 100 ml.). The sodium salt of thiobarbituric acid rapidly begins to separate. Fit the water-condenser with a calcium chloride guard-tube (Fig. 61, p. 105), and boil the mixture on the water-bath for 1 hour. Cool the mixture, filter off the sodium salt at the pump and wash it with a small quantity of cold acetone. Dissolve the salt in warm water and liberate the acid by the addition of 30 ml. of concentrated hydrochloric acid diluted with 30 ml. of water. Cool the mixture, filter off the thiobarbituric acid, and recrystallise it from hot water. Colourless crystals, m.p. 245 with decomposition (immersed at 230°). Yield, 3 5 -4 0 g. [Pg.307]

By hydrolysis of substituted malonic esters with 50 per cent, potassium hydroxide, followed by decarboxylation of the resulting malonic add by heating above the m.p. or, better, by rendering the aqueous solution of the potassium salt of the dibasic acid strongly acid and refluxing the mixture, for example ... [Pg.354]

The solution containing mineral acid should not be heated above 50-60 or diethyl malonate will be formed. [Pg.434]

Ootonic acid may be prepared by condensing acetaldehyde with malonic acid in pyridine solution in the presence of a trace of piperidine (Doebner reaction see discussion following Section IV,123). [Pg.463]

Mix together in a 250 ml. flask carrying a reflux condenser and a calcium chloride drying tube 25 g. (32 ml.) of freshly-distilled acetaldehyde with a solution of 59-5 g. of dry, powdered malonic acid (Section 111,157) in 67 g. (68-5 ml.) of dry pyridine to which 0-5 ml. of piperidine has been added. Leave in an ice chest or refrigerator for 24 hours. Warm the mixture on a steam bath until the evolution of carbon dioxide ceases. Cool in ice, add 60 ml. of 1 1 sulphuric acid (by volume) and leave in the ice bath for 3-4 hours. Collect the crude crotonic acid (ca. 27 g.) which has separated by suction filtration. Extract the mother liquor with three 25 ml. portions of ether, dry the ethereal extract, and evaporate the ether the residual crude acid weighs 6 g. Recrystallise from light petroleum, b.p. 60-80° the yield of erude crotonic acid, m.p. 72°, is 20 g. [Pg.464]

This preparation is another example of the condensation of an aldehyde with malonic acid and pyridine to 3neld ultimately an ap-unsaturated acid (Doebner reaction). It is included here because, unlike the acids prepared from many of the lower aUphatic aldehydes, the product consists largely (about 95 per cent.) of the ap-isomeride and only about 5 per cent, of the PY-isomeride is present ... [Pg.465]

Dissolve 57 g. of dry malonic acid in 92 5 ml. of dry P3rridine contained in a 500 ml. round-bottomed flask, cool the solution in ice, and add 57 g. (70 ml.) of freshly distilled n-heptaldehyde (oenanthol) with stirring or vigorous shaking. After a part of the aldehyde has been added, the mixture rapidly seta to a mass of crystals. Insert a cotton wool (or calcium chloride) tube into the mouth of the flask and allow the mixture to stand at room temperature for 60 hours with frequent shaking. Finally, warm the mixture on a water bath until the evolution of carbon dioxide ceases (about 8 hours) and then pour into an equal volume of water. Separate the oily layer and shake it with 150 ml. of 25 per cent hydrochloric acid to remove pyridine. Dissolve the product in benzene, wash with water, dry with anhydrous magnesium sulphate, and distil under reduced pressure. Collect the ap-nonenoic acid at 130-13272 mm. The yield is 62 g. [Pg.466]

Sorbic acid is prepared by the condensation of crotonaldehj de with malonic acid ill the presence of pyridine at 100° (Doebner reaction) ... [Pg.466]

This method of 93mthe8ising acids is rarely used since better yields are obtained with ethyl malonate (Section 111,155). [Pg.475]

Ethyl malonate can be conveniently prepared by neutralising a solution of monochloroacetic acid with sodium bicarbonate, then heating with potassium cyanide to form sodium cyanoacetate ... [Pg.483]

CHjClCOONa + KCN —> CHj(CN)COONa + KCl Upon warming the crude sodium cyanoacetate with ethyl alcohol and sulphuric acid, ethyl malonate is produced. Two mechanisms of the reaction have been proposed —... [Pg.483]

The monosubstituted malonic ester still possesses an activated hydrogen atom in its CH group it can be converted into a sodio derivative (the anion is likewise mesomeric) and this caused to react with an alkyl halide to give a C-disubstituted malonic ester. The procedure may accordingly be employed for the synthesis of dialkyImalonic and dialkylacetic acids ... [Pg.484]


See other pages where Malonic acid, malonate is mentioned: [Pg.287]    [Pg.136]    [Pg.375]    [Pg.103]    [Pg.368]    [Pg.317]    [Pg.1152]    [Pg.152]    [Pg.209]    [Pg.296]    [Pg.448]    [Pg.33]    [Pg.51]    [Pg.120]    [Pg.167]    [Pg.248]    [Pg.248]    [Pg.248]    [Pg.256]    [Pg.298]    [Pg.328]    [Pg.1100]    [Pg.1106]    [Pg.275]    [Pg.280]    [Pg.465]    [Pg.466]    [Pg.466]    [Pg.483]    [Pg.483]   
See also in sourсe #XX -- [ Pg.42 , Pg.222 , Pg.224 ]




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1,1-Dicarboxylic acids, decarboxylation from malonic esters

1.3- Dioxane-4,6-diones malonic acid esters

2- Cyclopentene-1-malonic acid, diethyl

2- Cyclopentene-1-malonic acid, diethyl ESTER

2- malonic acid formation

2-Nitrobenzaldehyde, in formation reaction with malonic acids

5,5-acetal acetamido)malonic acid diethyl

Acetic acid malonic ester synthesis

Acid chlorides, reaction with malonate enolates

Acidity continued malonic acid

Acidity malonic ester

Acidity of diethyl malonate

Anodic Dimerization of Malonic Acid Derivatives

Aqueous malonic acid

Aqueous reactions malonic acid

Aromatic acids from malonic ester

Asymmetric transformation of malonic acid derivative

Benzal-malonic acid

Benzyl-malonic acid

Benzylidene malonic acid

Bromination of malonic acid

Butyl acetate malonic acid

Cadmium complexes malonic acid

Calcium complexes malonic acid

Carboxylic acid amid malonic

Carboxylic acid from malonic ester

Carboxylic acid malonic ester synthesis

Carboxylic acids by malonic ester synthesis

Carboxylic acids, from malonic acid derivatives

Carboxylic acids-alkenes => malonic

Chlorine dioxide-iodide-malonic acid

Chlorine dioxide-iodide-malonic acid reaction

Chlorine dioxide-iodine-malonic acid

Chlorine dioxide-iodine-malonic acid CDIMA) reaction

Chlorite-iodide-malonic acid

Chlorite-iodide-malonic acid reaction

Chlorite-iodide-malonic acid reaction, Turing patterns

Chlorite-iodine-malonic acid reaction

Copper complexes malonic acid

Decarboxylation malonic acid derivatives

Decarboxylation of Malonic Acid and Related Compounds

Decarboxylation of malonic acid derivatives

Decarboxylation of malonic acids

Decarboxylation reactions malonic acid

Decarboxylation, ketoester malonic acid

Diethyl ester of malonic acid

Diethyl malonate acidity

Diethyl malonate, alkylation carboxylic acids from

Dimethyl malonic acid

Dimethyl methoxymethylenemalonate: Malonic acid,

Electronic structure malonic acid

Enantioselective malonic acid synthesis

Enantioselective substituted malonic acid

Enolate anions, malonic acid, reaction with

Enolate anions, malonic acid, reaction with aldehydes

Esterification, by azeotropic distillation of malonic acid with isobutylene

Esters, carboxylic acid malonic

Ethoxymethylene malonic acid diethyl ester

Ethyl malonic acid

Ethyl malonic acid ester

Ethyl methyl malonic acid

Ethyl, amine malonic acid

Fluorination of monalkyl malonic acid

From malonic ester acid synthesis

Half ester, of malonic acid

Hydroxy aldehydes malonic acid

Imines, reaction with malonic acid enolates

Isobutyl malonic acid dimethyl ester

Knoevenagel condensation with malonic acid

Lead acetate Malonic acid

Maleic acid Malonic ester

Malonates, acidity

Malonates, acidity

Malonic acid

Malonic acid

Malonic acid 2-bromo-2- -, diethyl ester

Malonic acid Claisen condensation

Malonic acid Derivatives

Malonic acid Homologues

Malonic acid Knoevenagel reaction

Malonic acid Reactions

Malonic acid acidity

Malonic acid acidity

Malonic acid acids

Malonic acid acids

Malonic acid alkylation

Malonic acid amides

Malonic acid amides barbituric acids

Malonic acid amides esters

Malonic acid amides lactones

Malonic acid and derivatives

Malonic acid aryl esters

Malonic acid aryl esters cyclic

Malonic acid as reagent esters

Malonic acid benzaldehyde reaction

Malonic acid bromination

Malonic acid chromium complexes

Malonic acid complexes

Malonic acid decarboxylation

Malonic acid decarboxylative

Malonic acid derivatives saponification

Malonic acid derivatives, additions

Malonic acid derivatives, oxidative dimerization

Malonic acid diamide

Malonic acid dibromide

Malonic acid dibromide via oxalyl bromide

Malonic acid diethyl ester

Malonic acid diethyl ester, preparation

Malonic acid dimethyl ester

Malonic acid dinitrile

Malonic acid drying

Malonic acid enolates

Malonic acid enolization

Malonic acid ester

Malonic acid ester, preparation

Malonic acid ethylhydroxy

Malonic acid halogenation

Malonic acid inhibition

Malonic acid l,3-dioxane-4,6-diones

Malonic acid metal complexes

Malonic acid methyl ester

Malonic acid mono-ethyl ester

Malonic acid monoamide

Malonic acid monoesters

Malonic acid monoethyl ester

Malonic acid naturally occurring

Malonic acid optically active

Malonic acid pathway

Malonic acid photolysis

Malonic acid plants

Malonic acid preparation

Malonic acid reduction

Malonic acid stability

Malonic acid structure

Malonic acid substituted

Malonic acid syntheses

Malonic acid synthesis intramolecular

Malonic acid, 2-amino-2-methyl

Malonic acid, 2-amino-2-methyl synthesis

Malonic acid, 2-bromo-2- -, diethyl

Malonic acid, 2-bromo-2- -, diethyl preparation

Malonic acid, 290 (Table

Malonic acid, Hydroxy

Malonic acid, Nitro

Malonic acid, Oxo

Malonic acid, acetamido-, diethyl

Malonic acid, acetamido-, diethyl ESTER

Malonic acid, alkylsynthesis

Malonic acid, alkylsynthesis via disubstituted organopotassium compounds

Malonic acid, amino-, diethyl ester

Malonic acid, amino-, diethyl ester HYDROCHLORIDE

Malonic acid, benzal-, diethyl

Malonic acid, benzal-, diethyl ESTER

Malonic acid, benzoyl, diethyl

Malonic acid, benzoyl, diethyl ESTER

Malonic acid, benzylidenedimethyl ester

Malonic acid, benzylidenedimethyl ester 3 + 2] cycloaddition reactions

Malonic acid, bis

Malonic acid, bis -, diethyl ester

Malonic acid, cetyl-, diethyl ester

Malonic acid, chiral

Malonic acid, condensation reactions

Malonic acid, cyclic isopropylidene ester

Malonic acid, derivation

Malonic acid, diethyl ester intramolecular alkylation

Malonic acid, enolate, reaction with

Malonic acid, enolate, reaction with aldehydes

Malonic acid, ethoxymethylene

Malonic acid, ethyl half ester

Malonic acid, ethylhydroxy-, diethyl ester, benzoate

Malonic acid, ethylidene, diethyl

Malonic acid, ethylidene, diethyl ESTER

Malonic acid, half-ester, reaction with

Malonic acid, methylenediesters

Malonic acid, methylenediesters Diels-Alder reactions

Malonic acid, methylenediesters cycloaddition reactions

Malonic acid, methylenediesters dimenthyl ester

Malonic acid, methylenediesters dimethyl ester

Malonic acid, methylenediesters synthesis via retro Diels-Alder reaction

Malonic acid, monoethyl ester, potassium

Malonic acid, monoethyl ester, potassium salt

Malonic acid, oxodialkyl esters

Malonic acid, oxodialkyl esters diethyl ester

Malonic acid, oxodialkyl esters ene reaction

Malonic acid, periodate oxidation

Malonic acid, substituted bromination

Malonic acid, substituted decarboxylation

Malonic acid, sulfate

Malonic acid, thioxodiethyl ester

Malonic acid, thioxodiethyl ester Diels-Alder reactions

Malonic acid: Doebner reaction with

Malonic acids Mannich bases

Malonic acids amine-catalyzed condensation reactions

Malonic acids aryl derivatives

Malonic acids oxidative decarboxylation

Malonic acids substituent effect

Malonic acids, cyclic

Malonic acids, decarboxylation formation

Malonic acids, ionization

Malonic ester acid synthesis

Malonic ester synthesis of carboxylic acids

Malonic ester synthesis of substituted acetic acids

Malonic ester, carboxylic acids from decarboxylation

Malonic ketocarboxylic acid

Mechanism decarboxylation of malonic acid

Methyl ethyl ketone malonic acid

Methyl ketone, from acids, malonate

Methyl malonic acid

Methyl malonic acid metabolism

Methyl, alcohol malonic acid

Michael with malonic acid ester

Of malonic acid

Oxidation of Malonic Acid by Bromate (Belousov-Zhabotinskii Reaction)

Phenyl ethyl malonic acid diethyl ester

Phenyl malonic acid

Producing Alkoxy Malonic Acid Dinitriles

Radicals malonic acids

Reaction with malonic acid chlorides

Reactions of Malonic Acid Derivatives

Ricinoleic acid reaction with malonic esters

Ring closure malonic acid esters

Secondary Products Derived from Cinnamic Acids and Malonate

Stereoselectivity, malonic acid

Stereoselectivity, malonic acid aldehydes

Succinic acid from malonic ester

Thioesters malonic acid

Ursolic acid hydrogen malonate

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