| Title:  Decalin® (DuPont) CAS Registry Number:  91-17-8 CAS Name:  Decahydronaphthalene Additional Names:  perhydronaphthalene;  bicyclo[4.4.0]decane;  naphthalane;  naphthane Trademarks:  DeKalin Molecular Formula:  C10H18 Molecular Weight:  138.25 Percent Composition:  C 86.88%, H 13.12% Literature References:  Occurs in two forms:  cis and trans.  Hydrogenation of naphthalene in glacial acetic acid in the presence of platinum catalyst at 25° and 130 atm yields a mixture of 77% cis-Decalin and 23% trans-Decalin.  Hydrogenation of Tetralin under the same conditions yields almost only cis-Decalin:  Baker, Schuetz, J. Am. Chem. Soc. 69, 1250 (1947).  Hydrogenation of D4a(8a)-octalin in ethanol in the presence of platinum yields trans-Decalin as the main component:  Linstead et al., J. Chem. Soc. 1937, 1136.  Separation of trans- and cis-forms:  Seyer, Walker, J. Am. Chem. Soc. 60, 2125 (1938).  Prepn of trans-Decalin from cis-Decalin:  Zelinsky, Ber. 65, 1299 (1932).  Conformation studies:  Barton, J. Chem. Soc. 1948, 340; Moniz, Dixon, J. Am. Chem. Soc. 83, 1671 (1961).  Toxicity data:  Smyth et al., Arch. Ind. Hyg. Occup. Med. 4, 119 (1951). Properties:  Liquid.  Slight odor resembling menthol.  Pure Decalin does not smell of naphthalene.  Volatile with steam.  The commercial product may be practically all trans-Decalin, or a mixture contg up to 60% cis-Decalin.  The commercial mixture has a flash pt (closed cup) of about 136°F (58°C).  Autoignition temp 504°F.  Insol in water.  Very sol in alcohol, methanol, ether, chloroform.  Miscible with propyl and isopropyl alcohol; miscible with most ketones and esters.  LD50 orally in rats:  4.2 g/kg; LC (in air) in rats:  500 ppm (Smyth). Flash point:  flash pt (closed cup) of about 136°F (58°C) Toxicity data:  LD50 orally in rats:  4.2 g/kg; LC (in air) in rats:  500 ppm (Smyth)   Derivative Type:  cis-Form  Properties:  mp -43.26°.  bp 195.7°; bp9 67.0°.  d420 0.8963.  nD20 1.48113. Melting point:  mp -43.26° Boiling point:  bp 195.7°; bp9 67.0° Index of refraction:  nD20 1.48113 Density:  d420 0.8963   Derivative Type:  trans-Form  Properties:  mp -30.4°.  bp 187.25°; bp9 62.0°.  d420 0.8700.  nD20 1.46968. Melting point:  mp -30.4° Boiling point:  bp 187.25°; bp9 62.0° Index of refraction:  nD20 1.46968 Density:  d420 0.8700   Use:  Solvent for naphthalene, fats, resins, oils, waxes; used instead of turpentine in lacquers, shoe polishes, floor waxes.  In motor fuel and lubricants.  As patent fuel in stoves.  |