Tetramethylbutane

Tetramethylbutane

Names
IUPAC name 2,2,3,3-Tetramethylbutane
Identifiers
CAS Number	594-82-1 Y
3D model (Jmol)	Interactive image
ChemSpider	11185 N
ECHA InfoCard	100.008.961
EC Number	209-855-6
PubChem	11675
UN number	1325
InChI InChI=1S/C8H18/c1-7(2,3)8(4,5)6/h1-6H3 N Key: OMMLUKLXGSRPHK-UHFFFAOYSA-N N
SMILES CC(C)(C)C(C)(C)C
Properties
Chemical formula	C8H18
Molar mass	114.23 g·mol−1
Appearance	White, opaque, waxy crystals
Odor	Odorless
Melting point	98 to 104 °C; 208 to 219 °F; 371 to 377 K
Boiling point	106.0 to 107.0 °C; 222.7 to 224.5 °F; 379.1 to 380.1 K
Henry's law constant (kH)	2.9 nmol Pa−1 kg−1
Thermochemistry
Specific heat capacity (C)	232.2 J K−1 mol−1 (at 2.8 °C)
Std molar entropy (So298)	273.76 J K−1 mol−1
Std enthalpy of formation (ΔfHo298)	−270.3 – −267.9 kJ mol−1
Std enthalpy of combustion (ΔcHo298)	−5.4526 – −5.4504 MJ mol−1
Hazards
EU classification (DSD)	F Xn N
R-phrases	R11, R38, R65, R67, R50/53
S-phrases	(S2), S16, S29, S33
Flash point	4 °C (39 °F; 277 K)
Explosive limits	1–?%
Related compounds
Related alkanes	Neopentane 2,2-Dimethylbutane 2,3-Dimethylbutane Triptane Tetraethylmethane 2,2,4-Trimethylpentane 2,3,3-Trimethylpentane 2,3,4-Trimethylpentane Tetra-tert-butylmethane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Tetramethylbutane, sometimes called hexamethylethane, is a hydrocarbon with formula C₈H₁₈ or (H₃C-)₃C-C(-CH₃)₃. It is the most heavily branched and most compact of the many octane isomers, the only one with a butane (C4) backbone. Because of its highly symmetrical structure, it has a very high melting point and a short liquid range; in fact, it is the smallest saturated acyclic hydrocarbon that appears as a solid at a room temperature of 25 °C. (Among cyclic hydrocarbons, cubane, C₈H₈ is even smaller and is also solid at room temperature.)

The compound can be obtained by reaction of Grignard reagent tert-butylmagnesium bromide with ethyl bromide, or of ethylmagnesium bromide with tert-butyl bromide in the presence of manganese(II) ions. This transformation is believed to go through the dimerization of two tert-butyl radicals, which are generated by decomposition of the organomanganese compounds generated in situ.

The full IUPAC name of the compound is 2,2,3,3-tetramethylbutane, but the numbers are superfluous in this case because there is no other possible arrangement of "tetramethylbutane".