Title: Terpin
CAS Registry Number: 80-53-5
CAS Name: 4-Hydroxy-a,a,4-trimethylcyclohexanemethanol
Additional Names: p-menthane-1,8-diol; dipenteneglycol
Molecular Formula: C10H20O2
Molecular Weight: 172.26
Percent Composition: C 69.72%, H 11.70%, O 18.58%
Literature References: Both cis-and trans-modifications are known. The cis-compd is obtained most readily in the hydrated form, cis-terpin hydrate. Prepn of cis-form from oil of turpentine: Hempel, Ann. 180, 71 (1876); Wallach, Ann. 230, 225 (1885); Schmitt, Manuf. Chem. 26, 350 (1955). From d-limonene: Sword, J. Chem. Soc. 127, 1632 (1925). Prepn of trans-form from 1,8-cineole, a-terpineol or cis-terpin hydrate: Matsuura et al., Bull. Chem. Soc. Jpn. 31, 990 (1958); Lombard, Ambroise, Bull. Soc. Chim. Fr. 1961, 230. Structure of cis- and trans-forms: Baeyer, Ber. 26, 2861 (1893); Wagner, ibid. 27, 1636 (1894).
Derivative Type: cis-Form hydrate
CAS Registry Number: 2451-01-6
Additional Names: Terpin hydrate; terpinol
Properties: Rhombic pyramids from water, mp 116-117°; sublimes at ~100° when heated slowly; slight characteristic odor and slightly bitter taste; efflorescent in dry air. Anhydr cis-form: mp 104-105°; bp 258°; rapidly re-forms hydrate on exposure to air. One gram dissolves in 34 ml boiling water, 13 ml alcohol, 3 ml boiling alcohol, 135 ml chloroform, 140 ml ether, ~1 ml boiling glacial acetic acid. At 20°, one gram dissolves in 13 ml methanol, 13 ml ethyl acetate, 250 ml water, 77 ml benzene, 290 ml carbon tetrachloride, 250 ml carbon disulfide. Practically insol in petr ether.
Melting point: mp 116-117°; mp 104-105°
Boiling point: bp 258°
Derivative Type: trans-Form
CAS Registry Number: 565-50-4
Properties: Monoclinic prisms, mp 158-159°. One gram dissolves at 20° in 11 ml methanol, 20 ml ethyl acetate, 100 ml water, 250 ml benzene, 250 ml carbon tetrachloride, 500 ml carbon disulfide.
Melting point: mp 158-159°
Therap-Cat: cis-Form hydrate as expectorant.
Therap-Cat-Vet: Expectorant.
Keywords: Expectorant. |