Title: Pantolactone
CAS Registry Number: 599-04-2
CAS Name: Dihydro-3-hydroxy-4
H-dimethyl-2(3
H)-furanone
Synonyms: pantoic acid g-lactone; pantoyl lactone; pantoic lactone; 2,4-dihydroxy-3,3-dimethylbutyric acid g-lactone; a-hydroxy-b,b-dimethyl-g-butyrolactone
Molecular Formula: C6H10O3
Molecular Weight: 130.14
Percent Composition: C 55.37%, H 7.75%, O 36.88%
Literature References: A degradation product of pantothenic acid from liver: Williams, Major,
Science 91, 246 (1940). Important intermediate in the synthesis of pantothenic acid. May be prepd by condensing isobutyraldehyde with formaldehyde yielding a,a-dimethyl-b-hydroxypropionaldehyde which is condensed with hydrocyanic acid in the presence of calcium chloride to form racemic pantolactone. Various modifications of this procedure exist: Glaser,
Monatsh. Chem. 25, 46 (1904); Stiller
et al., J. Am. Chem. Soc. 62, 1785 (1940); Reichstein, Grüssner,
Helv. Chim. Acta 23, 650 (1940); Carter, Ney,
J. Am. Chem. Soc. 63, 312 (1941). Vast patent literature,
e.g., Beckmann
et al.; Klein,
US 2967869 and
US 3024250 (1961, 1962, both to Nopco).
Derivative Type: D(-)-Form
Properties: Hygroscopic crystals from benzene + petr ether, mp 92°. [a]D25 -50.7° (c = 2.05 in H2O). Can be purified by microsublimation.
Melting point: mp 92°
Optical Rotation: [a]D25 -50.7° (c = 2.05 in H2O)
Derivative Type: L(+)-Form
Properties: Hygroscopic crystals from benzene, mp 91°. [a]D25 +50.1° (c = 2 in H2O).
Melting point: mp 91°
Optical Rotation: [a]D25 +50.1° (c = 2 in H2O)
Derivative Type: DL-Form
Properties: Hygroscopic rosettes or prisms, mp 80°, bp18 130°. Freely sol in water. Sol in ether, benzene, chloroform, alcohol, carbon disulfide.
Melting point: mp 80°
Boiling point: bp18 130°