Alkyne

A molecule with a carbon-carbon triple bond, C≡C. A terminal alkyne, R-C≡C-H is bonded to carbon on one end and a hydrogen on the other. An internal alkyne , R-C≡C-R has both ends bonded to carbon. Terminal alkynes are notable for being unusually acidic (pK_a 25) due to the s-hybridization of the carbon atom.

Glossary: Hg(OAc)2
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