DIMETHYLANILINE

CASRN: 121-69-7; DOT: 2253; molecular formula: C8H11N; FW: 121.18; RTECS: BX4725000; Merck Index: 12, 3284 Physical state, color, and odor: Straw to brown-colored oily liquid with a characteristic amine-like odor. Odor threshold concentration is 13 ppb (quoted, Amoore and Hautala, 1983). Melting point (°C): 2.45 (Weast, 1986) Boiling point (°C): 192-194 (Windholz et al., 1983) Density (g/cm3): 0.9557 at 20 °C (Weast, 1986) Diffusivity in water (x 10-5 cm2/sec): 0.77 at 20 °C using method of Hayduk and Laudie (1974) Dissociation constant, pKa: 5.1 at 25 °C (Golumbic and Goldbach, 1951) Flash point (°C): 61 (NIOSH, 1997) Entropy of fusion (cal/mol⋅K): 9.91 (Tsonopoulos and Prausnitz, 1971) Heat of fusion (kcal/mol): 2.73 (Tsonopoulos and Prausnitz, 1971) Henry’s law constant (x 10-6 atm⋅m3/mol): 4.98 at 20 °C (approximate - calculated from water solubility and vapor pressure) Ionization potential (eV): 7.12 (Franklin et al., 1969) Soil organic carbon/water partition coefficient, log Koc: 2.26 (quoted, Meylan et al., 1992) Octanol/water partition coefficient, log Kow: 2.30 (HPLC, Unger et al., 1978)

2.62 at pH 7.4 (Rogers and Cammarata, 1969) Solubility in organics: Soluble in acetone, alcohol, benzene, chloroform, and ether (Weast, 1986) Solubility in water: 1,105.2 mg/L at 25 °C (shake flask-GC, Chiou et al., 1982) Vapor density: 4.95 g/L at 25 °C, 4.18 (air = 1) Vapor pressure (mmHg): 0.5 at 20 °C, 1.1 at 30 °C (quoted, Verschueren, 1983) 0.52 at 25 °C (Banerjee et al., 1990) Environmental fate: Photolytic. A rate constant of 1.48 x 10-10 cm3/molecule⋅sec was reported for the reaction of N,N-dimethylaniline and OH radicals in air at room temperature (Atkinson et al., 1987). Chemical/Physical. Products identified from the gas-phase reaction of ozone with N,Ndimethylaniline in synthetic air at 23 °C were: N-methylformanilide, formaldehyde, formic acid, hydrogen peroxide, and a nitrated salt having the formula: [C6H6NH(CH3)2]+NO3-(Atkinson et al., 1987). Reacts with acids forming water-soluble salts. Exposure limits: NIOSH REL: TWA 5 ppm (25 mg/m3), STEL 10 ppm (50 mg/m3), IDLH 100 ppm; OSHA PEL: TWA 5 ppm; ACGIH TLV: TWA 5 ppm, STEL 10 ppm (adopted). Toxicity: LC50 (48-h) for red killifish 275 mg/L (Yoshioka et al., 1986). Acute oral LD50 for rats 1,410 mg/kg (Yoshioka et al., 1986). Uses: Manufacture of vanillin, Michler’s ketone, methyl violet, and other dyes; solvent; reagent for methyl alcohol, hydrogen peroxide, methyl furfural, nitrate, and formaldehyde; chemical intermediate; stabilizer; reagent.