2-Methylhexane Property

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℃）

LogP

4.118 (est)

CAS DataBase Reference

591-76-4(CAS DataBase Reference)

EPA Substance Registry System

2-Methylhexane (591-76-4)

Safety

Hazard Codes 

F,Xn,N

Risk Statements 

11-38-50/53-65-67

Safety Statements 

9-16-29-33-60-61-62

RIDADR 

UN 3295 3/PG 2

WGK Germany 

3

RTECS 

MO3871500

Autoignition Temperature

536 °F

HazardClass 

3.1

PackingGroup 

II

HS Code 

29011000

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H225Highly Flammable liquid and vapour

H304May be fatal if swallowed and enters airways

H315Causes skin irritation

H336May cause drowsiness or dizziness

H410Very toxic to aquatic life with long lasting effects

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P233Keep container tightly closed.

P273Avoid release to the environment.

P301+P310IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P331Do NOT induce vomiting.

2-Methylhexane Chemical Properties,Usage,Production

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).

Uses

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.

Uses

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.]