Diphenylacetylene


Diphenylacetylene is the chemical compound C6H5C≡CC6H5. The molecule consists of phenyl groups attached to both ends of an alkyne. It is a colorless crystalline material that is widely used as a building block in organic synthesis and as a ligand in organometallic chemistry.

Preparation

In one preparation for this compound, benzil is condensed with hydrazine to give the bis, which is oxidized with mercury oxide. Alternatively stilbene is brominated, and the resulting dibromodiphenylethane is subjected to dehydrohalogenation, Yet another method starts involves the coupling iodobenzene and the copper salt of phenylacetylene in the Castro-Stephens coupling.

Derivatives

Reaction of Ph2C2 with tetraphenylcyclopentadienone results in the formation of hexaphenylbenzene. Reaction of Ph2C2 with benzal chloride in the presence of potassium t-butoxide affords the 3-alkoxycyclopropene which coverts to the cyclopropenium ion.