[Alias] Carrot acid, beet acid, malic acid, methanedipic acid.
[Molecular formula]C3H4O4
[Structural formula]HOOCCH2COOH
[Property] Malonic acid is a colorless, odorless crystal that is easy to absorb moisture. It was first discovered in the separation of the oxidation products of malic acid; hence the common name malic acid. It rarely exists in free form in nature. There are three crystal forms at room temperature, but only one monoclinic form exists above 94°C. The relative density is 1.619 (16°C), the melting point is 135.6°C (a small amount of sublimation), and the boiling point is 140°C (decomposition). Soluble in water, ethanol, methanol, isopropanol, soluble in pyridine and ether, slightly soluble in benzene. The aqueous solution is acidic. Malonic acid can form double salts or complex salts with various metals, and is easily decarboxylated by heating to decompose into acetic acid and carbon dioxide. Malonic acid is a strong acid that has a strong irritating effect on the skin and mucous membranes, but not as severe as oxalic acid.
[Application] Used as raw material for organic synthesis. Used in the pharmaceutical industry for the production of barbiturates and other drugs. It is used in the manufacture of spices, adhesives, and fungicides. It is also used as a surface treatment agent for leather and aluminum products, an electroplating polishing agent, a foaming agent for foam plastics, a cleaning agent for nuclear reactors, a thermal welding flux, and an explosive control agent.
[Brief preparation method] It is prepared by the reaction of sodium chloroacetate and sodium cyanide through substitution and hydrolysis.
[Safety and Protection] Malonic acid is low-toxic, packed in woven bags lined with plastic bags, each bag has a net weight of 25kg. Store and transport according to general chemical regulations. It is irritating to the skin and mucous membranes, just rinse with water when touching the skin.