Alkyne metathesis with simple catalyst systems: High yield dimerization of propynylated aromatics; scope and limitations

Article abstract of DOI:10.1016/S0040-4039(99)00282-8

High yield dimerization of propynylated benzenes and propynylnaphthalene by a mixture of Mo(CO)₆ and 4-chlorophenol at 140 °C in 1,2-dichlorobenzene is reported to give the corresponding disubstituted alkynes. The scope and limitation of the reaction and the influence of substitution pattern and substitution type are discussed. Oxygen or nitrogen carrying substrates metathesize in moderate to good yields and ortho-alkyl substituted examples form the respective tolanes very efficiently.