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| | 2,4-DIMETHYLPENTANE Basic information |
| | 2,4-DIMETHYLPENTANE Chemical Properties |
| Melting point | −123 °C(lit.) | | Boiling point | 80 °C(lit.) | | density | 0.673 g/mL at 25 °C(lit.) | | vapor density | 3.48 (vs air) | | vapor pressure | 3.29 psi ( 37.7 °C) | | refractive index | n20/D 1.381(lit.) | | Fp | 10 °F | | solubility | Soluble in acetone, benzene, chloroform, alcohol and ether. | | form | neat | | pka | >14 (Schwarzenbach et al., 1993) | | color | Colorless to Almost colorless | | explosive limit | ~7% | | Odor Threshold | 0.94ppm | | Water Solubility | 4.41mg/L(25 ºC) | | BRN | 1696855 | | Henry's Law Constant | 2.94(atm?m3/mol) at 25 °C (Mackay and Shiu, 1981) | | Exposure limits | ACGIH: TWA 400 ppm; STEL 500 ppm | | CAS DataBase Reference | 108-08-7(CAS DataBase Reference) | | EPA Substance Registry System | 2,4-Dimethylpentane (108-08-7) |
| | 2,4-DIMETHYLPENTANE Usage And Synthesis |
| Chemical Properties | Colorless liquid with an odor resembling heptane. An odor threshold concentration of 940 ppbv
was reported by Nagata and Takeuchi (1990). | | Uses | It is not only used for synthesizing WeiNiGuan, but also used in binder and coating industry. It is used for synthesizing resin fiber. It is also used as intermediates and adhesives in oil drop coagulation thickener. | | Source | In diesel engine exhaust at a concentration of 0.3% of emitted hydrocarbons (quoted,
Verschueren, 1983). Schauer et al. (1999) reported 2,4-dimethylpentane in a diesel-powered
medium-duty truck exhaust at an emission rate of 410 μg/km.
California Phase II reformulated gasoline contained 2,2-dimethylbutane at a concentration of
15,700 mg/kg. Gas-phase tailpipe emission rates from gasoline-powered automobiles with and
without catalytic converters were 2.92 and 354 mg/km, respectively (Schauer et al., 2002). | | Environmental fate | Photolytic. Based on a photooxidation rate constant of 5.0 x 10-12 cm3/molecule?sec for the
reaction of 2,3-dimethypentane and OH radicals in air, the half-life is 27 h (Alltshuller, 1991).
Chemical/Physical. Complete combustion in air yields carbon dioxide and water vapor. 2,4-
Dimethylpentane will not hydrolyze because it has no hydrolyzable functional group. | | Purification Methods | Extract it repeatedly with conc H2SO4, wash with water, dry and distil it. Alternatively percolated it through silica gel (previously heated in nitrogen to 350o). Purify it by azeotropic distillation with EtOH, followed by washing out the EtOH with water, drying and distilling. [Beilstein 1 IV 406.] |
| | 2,4-DIMETHYLPENTANE Preparation Products And Raw materials |
| Raw materials | 3,3-DIMETHYLHEXANE-->2,2,3-TRIMETHYLPENTANE-->3-ETHYL-2-METHYLPENTANE-->3,4-DIMETHYLHEXANE-->2,3-Dimethylpentane-->2,2-DIMETHYLHEXANE-->2,3,4-TRIMETHYLPENTANE-->2,2,3-TRIMETHYLBUTANE-->2-METHYLHEPTANE-->3-METHYLPENTANE-->2,3,3-TRIMETHYLPENTANE-->1-BUTENE-->3-Hexene, 2,5-dimethyl-3,4-bis(1-methylethyl)--->Cyclohexane, methyl-, radical ion(1+)-->2,3,3-TRIMETHYLHEXANE-->2,4-DIMETHYL-2-PENTENE-->2,3,3-TRIMETHYL-1-BUTENE |
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