propyne

Propyne, also known as methylacetylene, is an organic chemical with the formula C3H4. It is a terminal alkyne with the structure HC≡C-CH3, and its IUPAC name is prop-1-yne. As a small alkyne, it serves as a simple building block in organic synthesis and as a feedstock for various acetylenic transformations.

Production and uses

Propyne is produced as a byproduct in petroleum refining and from specialized syntheses of acetylene derivatives. It is used as a chemical intermediate to prepare propargyl compounds via deprotonation to form acetylide anions, which can undergo alkylation or coupling reactions. It also participates in cycloadditions and other reactions that form complex propargyl-containing structures. In some contexts, it is encountered as a reactive gas in industrial processes rather than a bulk material.

Properties

Propyne is a colorless, flammable gas at room temperature. It is more soluble in organic solvents than in water. As a terminal alkyne, its C–H bond is relatively acidic (the terminal hydrogen can be deprotonated by strong bases to give acetylide ions). The molecule can undergo typical alkyne additions, including hydrohalogenation and hydrogenation, and it can polymerize under certain conditions if not stabilized.

Safety and handling

Propyne should be handled with appropriate precautions for a flammable gas. It is stored under suitable pressure or in pressurized cylinders away from sources of ignition and oxidizers. Proper ventilation and standard gas-handling practices are required to minimize fire and explosion risk.