2-methyl-2-butene

Structural formula
General
Surname	2-methyl-2-butene
other names	2-methylbut-2-ene ( IUPAC ); Trimethylethylene; beta-isoamylene;
Molecular formula	C 5 H 10
Brief description	colorless liquid with a sweet odor
External identifiers / databases
EC number	208-156-3
ECHA InfoCard	100.007.416
PubChem	10553
Wikidata	Q2187069
properties
Molar mass	70.13 g mol −1
Physical state	liquid
density	0.66 g cm −3
Melting point	−134 ° C
boiling point	38 ° C
Vapor pressure	509 hPa (20 ° C); 745 hPa (30 ° C); 1060 hPa (40 ° C); 1470 hPa (50 ° C);
solubility	very sparingly soluble in water (0.19 g l −1 at 25 ° C); miscible with ethanol, benzene, ligroin, ethylene oxide and ether;
Refractive index	1.3870 (20 ° C)
safety instructions
H and P phrases	H: 225-302-304-315-336-341-351-411
	P: 201-210-273-301 + 310-304 + 340 + 312-331
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

2-methyl-2-butene (according to IUPAC nomenclature: 2-methylbut-2-en , also known under the name β-isoamylene ) is an organochemical compound from the group of aliphatic , unsaturated hydrocarbons . It is a structural isomer of the pentenes .

Extraction and presentation

2-Methyl-2-butene can be obtained from 2-methyl-2-butanol or neopentanol by dehydration .

properties

2-methyl-2-butene is a highly flammable, volatile, colorless liquid with a sweetish odor that is very difficult to dissolve in water.

Safety-related parameters

2-methyl-2-butene forms highly flammable vapor-air mixtures. The compound has a flash point of −45 ° C. The explosion range is between 1% by volume as the lower explosion limit (LEL) and 9% by volume as the upper explosion limit (UEL). The limit gap width was determined to be 0.96 mm (50 ° C). This results in an assignment to explosion group IIA. The ignition temperature is 290 ° C. The substance therefore falls into temperature class T3.

use

2-Methyl-2-butene is used for the production of 3-bromo-2,3-dimethyl-1,1-dicyan-butane in the presence of 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile) as a catalyst used. It is used as a precursor to peroxyacetyl nitrate for calibration purposes.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q Entry on 2-methyl-2-butene in the GESTIS substance database of the IFA , accessed on September 29, 2019(JavaScript required) .
↑ ^a ^b ^c data sheet 2-methyl-2-butene, tech. 90%, remainder mainly 2-methyl-1-butene at AlfaAesar, accessed on August 7, 2018 ( PDF )(JavaScript required) .
↑ Gnichtel, Horst: Organic chemistry. [Main volume] Walter de Gruyter, 1980, ISBN 978-3-11-082970-9 , pp. 688 ( limited preview in Google Book search).

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q Entry on 2-methyl-2-butene in the GESTIS substance database of the IFA , accessed on September 29, 2019(JavaScript required) .

[Alfa-2] ta sheet 2-methyl-2-butene, tech. 90%, remainder mainly 2-methyl-1-butene at AlfaAesar, accessed on August 7, 2018 ( PDF )(JavaScript required) .

[Gnichtel,_Horst-3] Gnichtel, Horst: Organic chemistry. [Main volume] Walter de Gruyter, 1980, ISBN 978-3-11-082970-9 , pp. 688 ( limited preview in Google Book search).