Overview
Chinese name: fumaric acid

English name: fumaric acid, trans-Butene dioic acid.
Molecular formula: C4H4O4.
Molecular weight: 116.07.
CAS :110-17-8.
Customs code: 29171900.00
EINECS :203-743-0. [1]
InChI code: InChI = 1/C4H4O4/c5-3 (6) 1-2-4 (7) 8/h1-2H, (H, 5,6) (H, 7,8) / b2-1 [2]
The simplest unsaturated dicarboxylic acids. Also known as fumaric acid or fumaric acid. First found from the Corydalis, in addition, there are a variety of mushrooms and fresh beef. Fumaric acid and maleic acid geometric isomers of each other, fumaric acid heated to 250-300 ℃ into maleic acid. Fumaric acid can generate unary and binary ester or amide, but does not generate one yuan chloride. With phosphorus pentachloride or thionyl chloride reaction of two yuan chloride. Fumaric acid by potassium permanganate oxidation of racemic tartaric acid.

Physical and chemical indicators
Appearance: colorless crystals.
Melting point: 300 ~ 302 ℃ (sealed tube), in 165 ℃ (17 mm Hg) distillation.
Melting point: 299 ~ 300 ℃
Relative density: 1.635 (20 / 4 ℃).
Solubility: soluble in water, slightly soluble in cold water, ether, benzene, soluble in water, soluble in ethanol. The chemical properties of fumaric acid and maleic acid are similar.