1Buten3yne

1-Buten-3-yne, also known as vinylacetylene, is an organic compound with the chemical formula C4H4. It is a colorless gas at room temperature and pressure. The molecule contains both a double bond and a triple bond, making it an unsaturated hydrocarbon. Specifically, it is an alkyne and an alkene. Its structure can be represented as CH2=CH−C≡CH.

1-Buten-3-yne is a reactive molecule due to the presence of both the alkene and alkyne functional groups. It can undergo various addition reactions characteristic of these unsaturated systems. For instance, the double bond can be hydrogenated to form butyne, and further hydrogenation yields butane. Similarly, the triple bond can also be hydrogenated.

This compound can be produced through various methods, including the dehydrohalogenation of dihalogenated butanes. It has been historically significant in the development of synthetic materials. For example, vinylacetylene was an intermediate in the production of neoprene, a synthetic rubber, through its dimerization and subsequent polymerization. While its direct use has declined with the development of newer synthetic routes, its chemistry remains an important topic in organic chemistry education. It is a flammable substance and should be handled with appropriate safety precautions.