Chloroacetic acid is used as raw material in Laboratories. It is neutralized by NaOH or Na2CO3 to generate chloroacetic acid sodium salt. The sodium salt reacts with KCN (or NaCN) to yield α-cyano sodium acetate. And then malonic acid can be prepared after alkaline hydrolysis, calcium replacement and acidification. Chemical reaction equation is as follows:
Malonic acid is a carboxylic acid. Carboxylic acids donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in Malonic acid to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions Malonic acid is incompatible with strong oxidizers. Malonic acid is also incompatible with bases and reducing agents.
Flash point data for Malonic acid are not available; however, Malonic acid is probably combustible.
Malonic acid is used as building block in chemical synthesis, specifically to introduce the molecular group -CH2-COOH. Product Data Sheet
Malonic acid is also known as methane dicarboxylic acid, carrot acid, malic acid reduction, beet acid. There are three kinds of crystal forms, of which two are triclinic, and one is monoclinic. That crystallized from ethanol is white triclinic crystals. Its relative molecular mass is 104.06. The relative density is 1.631 (15 ℃). Melting point is 135.6℃. It decomposes to acetic acid and carbon dioxide at 140℃. It does not decompose at 1.067×103~1.333×103Pa vacuum, but directly sublimates. It is not soluble in benzene. It is soluble in water, and the solubility is respectively 61.1 (0 ℃), 73.5 (20 ℃), 92.6 (50 ℃) in water, and 57 (20 ℃)in ethanol, 5.7 (20 ℃) in diethyl ether. It is slightly soluble in pyridine. It can decompose to formic acid and carbon dioxide in case of potassium permanganate. Malonic acid is dibasic acid. It has a typical reactive of dibasic acids, such as that its methylene is active, and it can be an addition, alkylation, amination, halogenation reaction; its two carboxyl groups are very close and they can be dehydrated; esterification with alcohol; decarboxylation by heating; condensation with carbonyl compounds; addition with compounds that containing active double bonds. Hydroxyl in two carboxyl groups of malonic acid were all replaced by ethoxy (see substitution reaction) to produce diethyl malonate. Diethyl malonate is important raw materials in organic synthesis for dyes and drugs synthesis. Because its molecules containing active methylene, which can react with sodium alcohol to generate sodium malonate. Then sodium malonate reacts with a variety of lively halides to generate substituted malonate. Malonate can prepare various monocarboxylic acids, dicarboxylic acids, keto acids and other compounds by hydrolysis reaction to lose carboxyl. As substituted malonate reacts with urea to prepare a commonly used hypnotic barbiturates.
Since that malonic acid generates carbon dioxide and water after heated without pollution problems, it can be directly used as aluminum surface treatment agent; it is also the raw material in the production of pesticides fungicides Fujione, herbicides Alloxydim; malonic acid is used to prepare diuretic sulfinpyrazone medicine, anti-inflammatory drug phenylbutazone paraben, sedatives bromomethyl Jacinto goods in pharmaceutical industries. In addition, malonic acid and its esters are widely used as pharmaceutical intermediates, such as preparing barbiturates, vitamins B1 and B6, etc. Esters of malonic acid are commonly used in organic synthesis. It also can be used as binding agent, perfum, resin additive, electroplating polishing agent, welding flux and so on.
The above information is edited by the chemicalbook of Ge Qian.
White crystals or crystalline powder. Sublimes in vacuum.
ChEBI: An alpha,omega-dicarboxylic acid in which the two carboxy groups are separated by a single methylene group.
The preparation method is that firstly sodium carbonate aqueous solution is added chloroacetic acid in the reaction vessel to get sodium chloroacetate aqueous solution. And then 30% sodium cyanide solution is slowly dripped at a predetermined temperature to generate sodium cyanide. After the reaction of cyanide finishes, sodium hydroxide is added to hydrolyze under heating in order to form sodium malonate solution. After the solution is concentrated, added dropwise to generate malonic acid, filtered and dried, then the product is obtained.
1. It mainly can be used as pharmaceutical intermediates. It also can be used as perfumery, adhesives, resin additives, electroplating polishing agent and so on.
2. It can be used as complexing agent. It also can be used to prepare barbituric salt.
3. Malonic acid is the intermediate of fungicides isoprothiolane. It is also the intermediate of plant growth regulator ethychlozate.
4. Malonic acid and its esters is mainly used as perfumery, adhesives, resin additives, pharmaceutical intermediates, electroplating, polishing agent, explosion control agents, heat welding fluxing additives and the like. In the pharmaceutical industry, it can be used to produce phenobarbital, barbiturates, vitamin B1, vitamin B2, vitamin B6, phenylbutazone, amino acids and so on. Malonic acid can be used as the aluminum surface treatment agent since that malonic acid generates carbon dioxide and water after heated without pollution problems. At this point, it has a great advantage when compared with acidic treating agent like formic acid in the past.
5. It can be used as complexing agent in the determination of beryllium, copper, calibration standard alkaline solution, biochemical studies, organic synthesis, preparing barbiturates, gas chromatography analysis of the standard.
White crystals. It dissolves easily in water. And it is soluble in alcohol, ether and pyridine.
Crystallise malonic acid from *benzene/diethyl ether (1:1) containing 5% of pet ether (b 60-80o), wash with diethyl ether, then recrystallise it from H2O or acetone. Dry it under vacuum over conc H2SO4. [Beilstein 2 IV 1874.]
Air & Water Reactions