Phenylacetylene → 2-[(Phenyl)ethynyl]phenyl-2-propanone

Participants

Reaction Steps

A solution of 28.3 g (112 mmole) of 2-bromophenyl-2-propanone, 14.7 ml (134 mmole) of phenylacetylene, 1.8 g (2.24 mmole) of bis(triphenylphosphine)palladium (II) chloride and 0.85 g (4.48 mmole) of copper (I) iodide in 250 ml of triethylamine under nitrogen was heated under reflux for 31/2 hours. An additional 3.6 ml of phenylacetylene, 0.36 g of palladium complex and 0.1 g copper (I) iodide were added. The mixture was heated under reflux for 31/2 hours. An additional 5.0 ml of phenylacetylene, 0.36 g of palladium complex and 0.17 g of copper (I) iodide were added. The mixture was heated under reflux for 2 hours. An additional 5.0 ml of phenylacetylene was added. The mixture was heated under reflux for 31/2 hours. The solvent was evaporated in vacuo and the residue taken up in ether. The ether was washed with water and brine, dried (K2CO3) and the solvent evaporated in vacuo. The residue was flash chromatographed on silica gel with ethyl acetate:hexane, 9:1, as eluant. The solvent was evaporated from the major compound bearing fraction to afford 21.2 g (81% yield) of 1-[2-(phenylethynyl)phenyl]-2-propanone as an oil.

Provenance & Evidence