2-Methylhexane

Synonym(s):Isoheptane

CAS NO.：591-76-4
Empirical Formula: C7H16
Molecular Weight: 100.2
MDL number: MFCD00009487
EINECS: 209-730-6
SAFETY DATA SHEET (SDS)
Update Date: 2023-11-28 16:31:44

What is 2-Methylhexane?

Chemical properties

clear colorless liquid

Physical properties

Clear, colorless, flammable, watery liquid with an odor similar to pentane, 2-methylpentane, 3- methylpentane, hexane, and 3-hexane. An odor threshold concentration of 420 ppb_v was reported by Nagata and Takeuchi (1990).

The Uses of 2-Methylhexane

2-Methylhexane is mainly used as a model iso-alkane in studies relating to iso-alkane oxidation, vapor-liquid phase equilibria of heptane isomers and catalytic cracking.

The Uses of 2-Methylhexane

Organic synthesis.

Hazard

Flammable, dangerous fire risk, explosivelimits in air 1–6%.

Source

Schauer et al. (1999) reported 2-methylhexane in a diesel-powered medium-duty truck exhaust at an emission rate of 570 μg/km.
Schauer et al. (2001) measured organic compound emission rates for volatile organic compounds, gas-phase semi-volatile organic compounds, and particle-phase organic compounds from the residential (fireplace) combustion of pine, oak, and eucalyptus. The gas-phase emission rate of 2-methylhexane was 2.6 mg/kg of pine burned. Emission rates of 2-methylhexane were not measured during the combustion of oak and eucalyptus.
California Phase II reformulated gasoline contained 2-methylhexane at a concentration of 15.3 g/kg. Gas-phase tailpipe emission rates from gasoline-powered automobiles with and without catalytic converters were 2.88 and 372 mg/km, respectively (Schauer et al., 2002).

Environmental Fate

Biological. Riser-Roberts (1992) reported 2- and 5-methylhexanoic acids as metabolites by the microorganism Pseudomonas aeruginosa.
Photolytic. Based on a reported photooxidation reaction rate constant of 6.80 x 10^-12 cm³/molecule?sec with OH radicals, the half-life of 2-methylhexane is 25 h (Altshuller, 1990).
Chemical/Physical. Complete combustion in air produces carbon dioxide and water vapor. 2- Methylhexane will not hydrolyze because it does not contain a hydrolyzable functional group.

Purification Methods

Purify it by azeotropic distillation with MeOH, then wash it with water (to remove the MeOH), dry it over type 4A molecular sieves and distil it. [Beilstein 1 IV 397.]

Properties of 2-Methylhexane

Melting point:	-118 °C
Boiling point:	90 °C(lit.)
Density	0.679 g/mL at 25 °C(lit.)
vapor pressure	2.27 psi ( 37.7 °C)
refractive index	n20/D 1.384(lit.)
Flash point:	25 °F
storage temp.	Flammables area
solubility	Soluble in acetone, alcohol, benzene, chloroform, ligroin, and ether (Weast, 1986). Miscible with liquid aliphatic hydrocarbons.
form	Liquid
color	Clear colorless
explosive limit	~7%
Water Solubility	3.8 mg/L at 23 °C (Coates et al., 1985) 2.54 mg/kg at 25 °C (shake flask-GLC, Price, 1976)
BRN	1696856
Henry's Law Constant	0.512 atm?m³/mol at 26.9 °C, 0.311 at 35.0 °C, 0.256 at 45.0 °C (dynamic headspace, Hansen et al., 1995)
Dielectric constant	1.9（20℃）
CAS DataBase Reference	591-76-4(CAS DataBase Reference)
EPA Substance Registry System	2-Methylhexane (591-76-4)

Safety information for 2-Methylhexane

Signal word	Danger
Pictogram(s)	Flame Flammables GHS02 Exclamation Mark Irritant GHS07 Health Hazard GHS08 Environment GHS09
GHS Hazard Statements	H225:Flammable liquids H304:Aspiration hazard H315:Skin corrosion/irritation H336:Specific target organ toxicity,single exposure; Narcotic effects H410:Hazardous to the aquatic environment, long-term hazard
Precautionary Statement Codes	P210:Keep away from heat/sparks/open flames/hot surfaces. — No smoking. P233:Keep container tightly closed. P273:Avoid release to the environment. P331:Do NOT induce vomiting. P301+P310:IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician. P303+P361+P353:IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.