[1] Thus the malonate ion can be HOOCCH2COO− or CH2(COO)2−2. IDENTIFICATION: Malonic acid, which is also called propanedioic acid, is a colorless or white crystalline powder. carfenazine, chlorpheniramine, pyrilamine, methylergonovine, and thiethylperazine. In der Zahnmedizin wird Maleinsäure in selbstätzenden Adhäsivsystemen verwendet, um Dentin zu konditionieren. [14], Carbon suboxide is prepared by warming a dry mixture of phosphorus pentoxide (P4O10) and malonic acid. [29], Malonic acid is diprotic; that is, it can donate two protons per molecule. Dastidar TG, Netravali AN, "'Green' crosslinking of native starches with malonic acid and their properties."

14/418,940. It is very soluble in water. In der Natur ist L-Äpfelsäure meist in unreifen Früchten wie Äpfeln, Quitten, Weintrauben, Berberitzenbeeren, Vogelbeeren und Stachelbeeren, en… It occurs naturally in the air, and occurs because of engine emissions, wood fires and from cigarettes. L-Malic acid is the naturally occurring isomer of malic acid, found mainly in sour and unripe fruits. In another method (used as a classroom demonstration), maleic acid is transformed into fumaric acid through the process of heating the maleic acid in hydrochloric acid solution. National Institute of Standards and Technology, pKa Data Compiled by R. Williams (pdf; 77 kB), "Organic Acids Concentration in Citrus Juice from Conventional Versus Organic Farming", "Note sur un acide obtenu par l'oxydation de l'acide malique", "The Effect of Salicylic Acid on the Briggs-Rauscher Oscillating Reaction", "Ueber die der Sorbinsäure homologen, ungesättigten Säuren mit zwei Doppelbindungen", "1-N-Acylamino-1,3-dienes from 2,4-pentadienoic acids by the Curtius rearrangement: benzyl trans-1,3-butadiene-1-carbamate", "Malonate Inhibition of Oxidations in the Krebs Tricarboxylic Acid Cycle", "Studies on the Mechanism of Hydrogen Transport in Animal Tissues : VI. Malonic acid[2] is a naturally occurring substance found in many fruits and vegetables. a Bei längerem Erhitzen auf 150 °C sowie bei UV-Bestrahlung isomerisiert die Maleinsäure zur stabileren Fumarsäure. Although not practised commercially, maleic acid can be converted into maleic anhydride by dehydration, to malic acid by hydration, and to succinic acid by hydrogenation (ethanol / palladium on carbon). IDENTIFICATION: Maleic acid is a colorless, crystalline solid with a faint acidic odor and a strong astringent taste. Kurt Lohbeck, Herbert Haferkorn, Werner Fuhrmann and Norbert Fedtke "Maleic and Fumaric Acids" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000. Malic acid is present naturally in many plants, including flowers, fruits and vegetables, spices, and wine grapes. [6], Maleic acid is an industrial raw material for the production of glyoxylic acid by ozonolysis.[7]. It is used in a number of manufacturing processes as a high value specialty chemical including the electronics industry, flavors and fragrances industry,[3] specialty solvents, polymer crosslinking, and pharmaceutical industry. The melting point of maleic acid (135 °C) is also much lower than that of fumaric acid (287 °C). The name originates from the Greek word μᾶλον (malon) meaning 'apple'. [8] Light converts elemental bromine into a bromine radical, which attacks the alkene in a radical addition reaction to a bromo-alkane radical; and now single bond rotation is possible.

Malonic acid is very soluble in water. It occurs in many plants, including fruits and grains. Mit Maleinsäure können alle typischen Carbonylreaktionen wie Veresterungen oder Aminierungen durchgeführt werden. Again, the large difference in water solubility makes fumaric acid purification easy. Maleic acid is found naturally in ginseng, tobacco leaves, sour cherries, cacao and corn. In 2004, annual global production of malonic acid and related diesters was over 20,000 metric tons. When malonic acid itself is used, it is normally because the desired product is one in which a second step has occurred, with loss of carbon dioxide, in the so-called Doebner modification. Maleat darf nicht mit dem Säureanion der Äpfelsäure, dem Malat-Ion, oder dem Anion der Malonsäure, dem Malonat verwechselt werden. [22][23] Starch-based polymers comprised 38% of the global biodegradable polymers market in 2014 with food packaging, foam packaging, and compost bags as the largest end-use segments. [2] Das Anhydrid bildet beim Auflösen in Wasser dann wieder Maleinsäure. The maleate ion is useful in biochemistry as an inhibitor of transaminase reactions. The ionized form of malonic acid, as well as its esters and salts, are known as malonates. It is a component in tobacco. The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals, Institute for Occupational Safety and Health, Maleic Anhydride, Maleic Acid, and Fumaric Acid, "A Refinement of the Crystal Structure of Maleic Acid", Calculator: Water and solute activities in aqueous maleic acid, https://en.wikipedia.org/w/index.php?title=Maleic_acid&oldid=952583370, Pages using collapsible list with both background and text-align in titlestyle, Articles containing unverified chemical infoboxes, Creative Commons Attribution-ShareAlike License, This page was last edited on 23 April 2020, at 00:37. This observation was used to deduce the structure of the active site in succinate dehydrogenase. Industrially, however, malonic acid is produced by hydrolysis of dimethyl malonate or diethyl malonate. 2004 International Waterborne, High-Solids, and Powder Coatings Symposium. Malonic acid (IUPAC systematic name: propanedioic acid) is a dicarboxylic acid with structure CH2(COOH)2. Maleic acid may be used to form acid addition salts with drugs to make them more stable, such as indacaterol maleate. Maleinsäure ist der Trivialname für cis-Butendisäure (auch cis-Ethylendicarbonsäure oder Toxilsäure genannt), eine Dicarbonsäure. Some bacteria produce the enzyme maleate isomerase, which is used by bacteria in nicotinate metabolism. Maleic acid has a heat of combustion of -1,355 kJ/mol. Inhibition of this enzyme decreases cellular respiration.