prop2yne

Prop2yne, in common chemical terminology, refers to the compound known more formally as prop-2-yne. This name is not the standard IUPAC form; the preferred systematic name for the same structure is prop-1-yne. In practice, prop-2-yne is another way some sources have described the same molecule, which is more widely known as propyne or methylacetylene. The molecule has the formula C3H4 and is a linear, terminal alkyne.

Structure and properties

Prop-1-yne (the standard name for the same structure) features a carbon–carbon triple bond between the first and second carbon atoms, with a terminal hydrogen on the end carbon and a methyl group on the other end. The carbon atoms at the triple bond are sp-hybridized, giving a linear geometry around the triple bond. The compound is a colorless gas at room temperature and is highly flammable. It participates in typical alkyne chemistry, including deprotonation to form acetylide nucleophiles and addition reactions across the triple bond.

Occurrence and production

Prop-1-yne (prop-2-yne when encountered in nonstandard writes) occurs as a minor component in certain hydrocarbon streams and is produced industrially in small quantities as a byproduct of petroleum refining and the synthesis of other alkynes. It is commonly handled as a compressed gas in industrial settings.

Reactions and uses

As a terminal alkyne, it can be deprotonated to give acetylide ions, which serve as strong nucleophiles for alkylation and other carbon–carbon bond-forming steps. It can be hydrogenated to propene or fully to propane, and it participates in electrophilic additions across the triple bond, as well as radical-initiated reactions under appropriate catalysts. It is used as a building block in organic synthesis and in certain industrial processes, though it is less commonly encountered than more stable hydrocarbons.

Safety

Prop-1-yne/prop-2-yne is highly flammable and can form explosive mixtures with air. It should be stored away from oxidizers and heat, and handled in well-ventilated facilities with appropriate gas-delivery equipment and detectors.