Vinylacetylene

• Butenyne
• Vinylacetylene
• 1-butene -3-yne
• Monovinylacetylen
• But-1 -en -3-yne (IUPAC)

Gaseous

0.71 g · l-1 (0 ° C, 1013 hPa)

-92 ° C

5 ° C

250 kPa (25 ° C)

1.4161 ( 1 ° C)

Template: Infobox chemical / molecular formula search available

Butenyne, often referred to as vinyl acetylene is a colorless gas. It is an organic chemical compound and is the smallest representative of the enynes, a group of polyunsaturated hydrocarbons, which have structurally both alkene and Alkincharakter.

Production

In the laboratory, it is easiest by double dehydrohalogenation ( elimination) of 1,3- dichloro -2-butene accessible. Technically butenyne be produced by the dimerization of ethyne ( acetylene). Dimerization is promoted by the use of a Nieuwland catalyst ( copper ( I) chloride ) in an aqueous phase. Butenyne was first produced in greater amounts by employees of DuPont in 1931.

Properties

As a highly unsaturated compound, vinyl tends to spontaneous decay. It is not stable and not commercially available in pure form. For safety reasons it should be handled diluted with inert gases. Although it still bears no official hazardous material identification, so it is - like any gaseous hydrocarbon - to consider as extremely flammable. His air mixtures are explosive in certain concentration limits.

Other physical data

The critical temperature is 183 ° C.

Use

Vinylacetylene was previously used as an intermediate for the synthesis of chloroprene (2-chloro -1 ,3- butadiene). The chloroprene was prepared by addition of hydrogen chloride to butenyne.

Vinyl acetylene can be controlled to polymerize Polyvinylacetylen that is suitable for example as a starting material for carbon fibers.