An important chemical raw material:cis-Butenedioic acid

cis-Butenedioic acid, also known as maleic acid, with CAS number 110-16-7, is a very important organic chemical raw material. This article will briefly summarize the properties, uses and preparation methods of cis-butenedioic aci.

The properties of cis-butenedioic acid

The appearance of cis-butenedioic acid is colorless crystals, with a melting point of 137-140°C (lit.), a boiling point of 275°C, and a molecular weight of 116.0722. It is easily soluble in water, ethanol, and acetone. Maleic acid has a double bond and a carbonyl group at each end. It is chemically active and can undergo addition reactions, hydrogenation, hydration and dehydration, alkylation, nucleophilic reactions, isomerization, decomposition and decarboxylation, oxidation and Reduction and other reactions. This product has a strong irritating odor, is corrosive, and is irritating to the eyes, skin and mucous membranes. It is harmful to the body after inhalation, ingestion or absorption through the skin.

Uses of cis-butenedioic acid

cis-Butenedioic acid is mainly used to prepare fumaric acid, unsaturated polyester resins, synthetic resins, dyeing auxiliaries and grease preservatives, etc. It also has a wide range of applications in medicine, pesticides, and food. In terms of pesticides: cis-butenedioic acid is used to prepare insecticides (Marathon, Dajingsong), fungicides (captan, dibendan), etc..

Preparation of cis-butenedioic acid

Maleic acid (MA)|110-16-7| is the hydrolysis reaction product of maleic anhydride (MAH)|108-31-6|, and the two can be transformed under certain conditions, that is, maleic acid  is heated to 160°C and dehydrated to form maleic anhydride, and  maleic anhydride is hydrolyzed to form maleic acid when it meets with water. Therefore, usually benzene or butane and air are used as raw materials to prepare maleic anhydride, and then hydrolyzed to prepare maleic acid.