Title: Tropic Acid
CAS Registry Number: 529-64-6
CAS Name: a-(Hydroxymethyl)benzeneacetic acid
Synonyms: 2-phenylhydracrylic acid; a-phenyl-b-hydroxypropionic acid; tropaic acid; tropeic acid
Molecular Formula: C9H10O3
Molecular Weight: 166.17
Percent Composition: C 65.05%, H 6.07%, O 28.88%
Literature References: Degradation product of tropane alkaloids, esp atropine: Lossen,
Ann. 133, 351, 370 (1865). Resolution of isomers: McKenzie, Wood,
J. Chem. Soc. 115, 828 (1919). Absolute config of isomers: Fodor, Csepreghy,
ibid. 1961, 3222; Watson, Youngson,
J. Chem. Soc. Perkin Trans. 1 1972, 1597. Prepn: Sletzinger, Paulsen,
US 2390278 (1945 to Merck & Co.); Blicke,
US 2716650 (1955 to U. of Michigan);
DE 923426 (1955 to Sterling Drug). Biosynthetic studies: Louden, Leete,
J. Am. Chem. Soc. 84, 1510, 4507 (1962).
Derivative Type: (±)-Form
Properties: Needles or plates from water or benzene, mp 118°. K at 25° = 7.5′10-5. Absorption spectrum: Dobbie, Fox,
J. Chem. Soc. 103, 1194 (1913). 1 gram dissolves in 50 ml water; freely sol in boiling water; sol in alcohol, ether, slightly in benzene; practically insol in petr ether.
Melting point: mp 118°
Derivative Type: (+)-Form
Properties: mp 107°. [a]D20 +72° (c = 0.5 in water).
Melting point: mp 107°
Optical Rotation: [a]D20 +72° (c = 0.5 in water)
Derivative Type: (-)-Form
Properties: mp 126-128°. [a]D20 -72° (c = 0.5 in water).
Melting point: mp 126-128°
Optical Rotation: [a]D20 -72° (c = 0.5 in water)