Triptane

Not to be confused with triptan, a type of anti-migraine drug, Tryptan, a trade name of tryptophan, or triplane.

Triptane

Skeletal formula of triptane Ball-and-Stick model of triptane
Names
Preferred IUPAC name 2,2,3-Trimethylbutane[1]
Identifiers
CAS Number	464-06-2^Y
3D model (JSmol)	Interactive image
Beilstein Reference	1730756
ChemSpider	9649^Y
ECHA InfoCard	100.006.680
EC Number	207-346-3
PubChem CID	10044
UNII	40V943JDGR^Y
UN number	1206
CompTox Dashboard (EPA)	DTXSID7060047
InChI InChI=1S/C7H16/c1-6(2)7(3,4)5/h6H,1-5H3^Y Key: ZISSAWUMDACLOM-UHFFFAOYSA-N^Y
SMILES CC(C)C(C)(C)C
Properties
Chemical formula	C7H16
Molar mass	100.205 g·mol^−1
Appearance	Colorless liquid
Odor	Odorless
Density	0.693 g mL^−1
Melting point	−26 to −24 °C; −15 to −11 °F; 247 to 249 K
Boiling point	80.8 to 81.2 °C; 177.3 to 178.1 °F; 353.9 to 354.3 K
Vapor pressure	23.2286 kPa (at 37.7 °C)
Henry's law constant (kH)	4.1 nmol Pa^−1 kg^−1
Magnetic susceptibility (χ)	-88.36·10^−6 cm^3/mol
Refractive index (nD)	1.389
Thermochemistry
Heat capacity (C)	213.51 J K^−1 mol^−1
Std molar entropy (S^⦵298)	292.25 J K^−1 mol^−1
Std enthalpy of formation (ΔfH^⦵298)	−238.0 – −235.8 kJ mol^−1
Std enthalpy of combustion (ΔcH^⦵298)	−4.80449 – −4.80349 MJ mol^−1
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H225, H302, H305, H315, H336, H400
Precautionary statements	P210, P261, P273, P301+P310, P331
NFPA 704 (fire diamond)	0 3 0
Flash point	−7 °C (19 °F; 266 K)
Autoignition temperature	450 °C (842 °F; 723 K)
Explosive limits	1–7%
Related compounds
Related alkanes	Neopentane 2,2-Dimethylbutane 2,3-Dimethylbutane Tetramethylbutane 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). Infobox references

Triptane, or 2,2,3-trimethylbutane, is an organic chemical compound with the molecular formula C₇H₁₆ or (H₃C-)₃C-C(-CH₃)₂H. It is therefore an alkane, specifically the most compact and heavily branched of the heptane isomers, the only one with a butane (C₄) backbone.

It was first synthesized in 1922 by Belgian chemists Georges Chavanne (1875–1941) and B. Lejeune, who called it trimethylisopropylmethane.^[2][3]

Due to its high octane rating (112–113 RON, 101 MON^[4][5]) triptane was produced on alkylation units starting from 1943^[6] for use as an anti-knock additive in gasoline. It was extensively researched for this role and received the modern name in the late 1930s at a joint laboratory of NACA, National Bureau of Standards, US Army Air Corps and the Bureau of Aeronautics.^[7]

As of 2011, it was not a significant component of US automobile gasoline, present only in trace amounts (0.05–0.1%).^[8]

See also

• List of gasoline additives

References

1. "Triptan - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 26 March 2005. Identification and Related Records. Retrieved 11 March 2012.
2. Chavanne, G.; Lejeune, B. (March 1922). "Un nouvel heptane : le triméthylisopropylméthane". Bulletin de la Société Chimique de Belgique. 31 (3): 99–102 – via Internet Archive.
3. https://webbook.nist.gov/cgi/cbook.cgi?Source=1922CHA%2FLEJ98
4. Nash, Connor P.; Dupuis, Daniel P.; Kumar, Anurag; Farberow, Carrie A.; To, Anh T.; Yang, Ce; Wegener, Evan C.; Miller, Jeffrey T.; Unocic, Kinga A.; Christensen, Earl; Hensley, Jesse E.; Schaidle, Joshua A.; Habas, Susan E.; Ruddy, Daniel A. (2022-02-01). "Catalyst design to direct high-octane gasoline fuel properties for improved engine efficiency". Applied Catalysis B: Environmental. 301: 120801. Bibcode:2022AppCB.30120801N. doi:10.1016/j.apcatb.2021.120801. ISSN 0926-3373. OSTI 1827631.
5. Perdih, A.; Perdih, F. (2006). "Chemical Interpretation of Octane Number". Acta Chimica Slovenica. S2CID 55494502.
6. stason.org, Stas Bekman: stas (at). "10.1 The myth of Triptane". stason.org. Retrieved 2024-11-16.
7. Annual Report of the National Advisory Committee for Aeronautics. U.S. Government Printing Office. 1938. p. 28.
8. "Hydrocarbon Composition of Gasoline Vapor Emissions from Enclosed Fuel Tanks". nepis.epa.gov. United States Environmental Protection Agency. 2011.