Title:  Citraconic Acid 
CAS Registry Number:  498-23-7 
CAS Name:  (Z)-2-Methyl-2-butenedioic acid 
Additional Names:  methylmaleic acid 
Molecular Formula:  C5H6O4 
Molecular Weight:  130.10 
Percent Composition:  C 46.16%, H 4.65%, O 49.19% 
Literature References:  Obtained by carefully heating citric acid at about 175°.  Production of citraconic anhydride from itaconic acid:  Humphrey, US 2966498 (1960 to Pfizer).  Toxicity study:  P. M. Jenner et al., Food Cosmet. Toxicol. 2, 327 (1964). 
Properties:  Hygroscopic monoclinic crystals; characteristic odor.  d 1.62.  mp ~90° (dec).  Freely sol in water, alc, ether, slightly in chloroform.  Practically insol in benzene, petr ether.  LD50 in rats, mice (mg/kg):  1320, 2260 orally (Jenner). 
Melting point:  mp ~90° (dec) 
Density:  d 1.62 
Toxicity data:  LD50 in rats, mice (mg/kg):  1320, 2260 orally (Jenner)   |