substituted acetylene

chemical compound

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Substituted acetylenes are a class of unsaturated aliphatic hydrocarbons that contain a carbon-carbon triple bond. They are characterized by the general molecular formula C_nH_{2n \u2212 2}, with ethyne (C₂H₂) being the simplest example. Unlike alkanes, which undergo substitution reactions, alkynes primarily undergo addition reactions where atoms attach to the triple bond.12

Substituted acetylenes can act as ligands in organometallic compounds, bonding to metal atoms. The alkyl or aryl groups attached to the acetylene can increase the stability of these metal complexes. While acetylene itself is an industrially unimportant chemical compared to ethylene, substituted acetylenes are used in various chemical syntheses.31

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organometallic compound
Alkene and alkyne ligands
Substituted acetylenes form very stable polymetallic complexes in which the acetylene can be regarded as a four-electron donor. An example is η²-diphenylethynehexacarbonyldicobalt, in which four of the six electrons in the triple bond of the ethyene ligand, R―C≡C―R, are shared with the two cobalt atoms…
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Substituted acetylenes form very stable polymetallic complexes in which the acetylene can be regarded as a four-electron donor. An example is η²-diphenylethynehexacarbonyldicobalt, in which four of the six electrons in the triple bond of the ethyene ligand, R―C≡C―R, are shared with the two cobalt atoms…
Read More