Copper(I) acetylide, or cuprous acetylide, is an inorganic chemical compound with the formula Cu₂C₂. It is a heat and shock sensitive high explosive, more sensitive than silver acetylide. It is a metal acetylide. It is similar to silver acetylide and calcium carbide, though it is not called carbide in literature.

Copper acetylide can be prepared by passing acetylene gas through copper(I) chloride solution in presence of ammonia:

C₂H₂ + 2CuCl → Cu₂C₂ + 2HCl

The reaction product is a reddish precipitate. The reaction is used as a test for acetylene.

Copper acetylide is an intermediate in several organic chemistry reactions, eg. Sonogashira coupling or Cadiot-Chodkiewicz coupling.

Copper acetylide can form inside pipes made of copper or an alloy with high copper content, which may result in violent explosion. This was found to be the cause of explosions in acetylene plants, and led to abandonment of copper as a construction material in such plants. Copper catalysts used in petrochemistry can also possess a degree of risk under certain conditions.

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