Editing Cyclopropene (section)

===Syntheses of derivatives===
Treatment of nitrocyclopropanes with [[sodium methoxide]] eliminates the nitrite, giving the respective cyclopropene derivative. The synthesis of purely aliphatic cyclopropenes was first illustrated by the copper-catalyzed additions of carbenes to alkynes. In the presence of a copper catalyst, [[ethyl diazoacetate]] reacts with acetylenes to give cyclopropenes. 1,2-Dimethylcyclopropene-3-carboxylate arises via this method from [[2-butyne]]. Copper, as copper sulfate and copper dust, are among the more popular forms of copper used to promote such reactions.  [[Rhodium acetate]] has also been used.