3255. Dimethyl Phthalate

Nomenclature

CAS number: 131-11-3
1,2-Benzenedicarboxylic acid dimethyl ester; phthalic acid dimethyl ester; methyl phthalate; dimethyl 1,2-benzenedicarboxylate; DMP; Palatinol M; Fermine; Avolin; Mipax.
C10H10O4; mol wt 194.18.
C 61.85%, H 5.19%, O 32.96%.

Description and references

Prepd industrially from phthalic anhydride and methanol: Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed., 1975) pp 318-324. Metabolite of Gibberella fujikuroi: Cross et al., J. Chem. Soc. 1963, 2937. Toxicity data: J. H. Draize et al., J. Pharmacol. Exp. Ther. 93, 26 (1948).

Chemical structure

Properties

Oily liq. Slight aromatic odor. d15.615.6 1.196; d2020 1.1940; d2525 1.189. One gallon weighs 9.93 lbs. Flash pt 295°F (146°C). mp 5.5° (the commercial product freezes around 0°). bp760 283.7°; bp400 257.8°; bp200 232.7°; bp100 210.0°; bp60 194.0°; bp40 182.8°; bp20 164.0°; bp10 147.6°; bp5 131.8°; bp1.0 100.3°. Vapor pressure at 20° <0.0l mm. The vapor is heavy, d = 6.69 (air = l). nD20 1.5168. Viscosity at 25° = 17.2 cP. Heat of vaporization: 93.1 g-cal/g; heat of combustion: 119.7 kg-cal/mole. uv max (ethanol): 277 nm (E1%1cm 57.7). Miscible with alcohol, ether, chloroform. Practically insol in water (0.43 g/100 ml), petr ether, and other paraffin hydrocarbons. Soly in mineral oil at 20°: 0.34 g/100 g. LD50 in mice, rats, guinea pigs (ml/kg): 7.2, 6.9, 2.4 orally (Draize).

Caution

Potential symptoms of overexposure are irritation of eyes, upper respiratory system; stomach pain. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 114.

Use

Solvent and plasticizer for cellulose acetate and cellulose acetate-butyrate compositions. Insect repellent for personal protection against biting insects.