Production and Main Reactions
Racemic malic acid is produced industrially by the double hydration of maleic anhydride. In 2000, American production capacity was 5000 tonnes per year. Both enantiomers may be separated by chiral resolution of the racemic mixture, and the (S)- enantiomer may be specifically obtained by fermentation of fumaric acid.
Self-condensation of malic acid with fuming sulfuric acid gives the pyrone coumalic acid:
Malic acid was important in the discovery of the Walden inversion and the Walden cycle, in which (-)-malic acid first is converted into (+)-chlorosuccinic acid by action of phosphorus pentachloride. Wet silver oxide then converts the chlorine compound to (+)-malic acid, which then reacts with PCl5 to the (-)-chlorosuccinic acid. The cycle is completed when silver oxide takes this compound back to (-)-malic acid.
Read more about this topic: Malic Acid
Famous quotes containing the words production, main and/or reactions:
“[T]he asphaltum contains an exactly requisite amount of sulphides for production of rubber tires. This brown material also contains “ichthyol,” a medicinal preparation used externally, in Webster’s clarifying phrase, “as an alterant and discutient.””
—State of Utah, U.S. public relief program (1935-1943)
“I had one life. And what did I do? Wasted it in some palooka preliminaries in Spain, just before Hitler and Chamberlain warm up for the main event.”
—Billy Wilder (b. 1906)
“Separation anxiety is normal part of development, but individual reactions are partly explained by experience, that is, by how frequently children have been left in the care of others.... A mother who is never apart from her young child may be saying to him or her subliminally: “You are only safe when I’m with you.””
—Cathy Rindner Tempelsman (20th century)