Neopentane

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Neopentane

General
IUPAC preferred name	neopentane
Systematic name	2,2-dimethylpropane
Molecular formula	C₅H₁₂
SMILES	CC(C)(C)C
Molar mass	72.15 g mol⁻¹
Appearance	colorless gas
CAS number	[463-82-1]
Properties
Density and phase	? g/l, gas
Solubility in water	? g/100 ml (? °C)
Melting point	−18 °C (255 K)
Boiling point	10 °C (283 K)
Thermodynamic data
Std enthalpy change of formation, Δ_fH^o_gas	−168 kJ/mol
Std enthalpy change of combustion, Δ_cH°_gas	−3514 kJ/mol
Standard molar entropy, S°_liquid	217 J·K⁻¹·mol⁻¹
Hazards
MSDS	External MSDS
EU classification	Highly flammable (F+) Dangerous for the environment (N)
NFPA 704	4 1 0
R-phrases	R12, R51/53
S-phrases	S2, S9, S16, S33, S61
Flash point	flammable gas
Supplementary data page
Structure and properties	n, ε_r, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Related alkanes	Pentane Isopentane
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Neopentane, also called dimethylpropane or 2,2-dimethylpropane, is a double-branched-chain alkane with five carbon atoms. Neopentane is an extremely flammable gas at room temperature and pressure which can condense into a highly volatile liquid on a cold day, in an ice bath, or when compressed to a higher pressure.

1 Nomenclature
2 Isomers
3 Proton NMR spectrum
4 Reference
5 External links

[edit] Nomenclature

IUPAC nomenclature retains the trivial name neopentane.^[1] Dimethylpropane is the systematic name. The respective substituent numbers (the 2,2-) are unnecessary because there can be no isomers of this molecule with dimethylpropane as part of their names.

A neopentyl substituent or a neopentyl compound has the structure Me₃C-CH₂- for instance neopentyl alcohol.

[edit] Isomers

Neopentane is one of three structural isomers with the molecular formula C₅H₁₂, the others being pentane and isopentane.

[edit] Proton NMR spectrum

Neopentane has T_d symmetry. As a result, all protons are chemically equivalent leading to a single chemical shift at δ 0.902 in carbon tetrachloride.^[2] This is similar to the silane analog, tetramethylsilane which has a single chemical shift, defined as δ 0 by convention.