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

Participants

Reaction Steps

To a 3-necked, round bottom flask under nitrogen was added 4.0 g (18.8 mmole) of 2-bromophenyl-2-propanone in 40 ml of triethylamine, 2.5 ml (22.5 mmole) of phenylacetylene, 0.3 g (2 mole %) of bis-(triphenylphosphine) palladium dichloride and 0.14 g (4 mole %) of cuprous iodide. After refluxing for three hours another 0.5 ml (4.5 mmole) of phenylacetylene, 0.6 g (4 mole %) of bis (triphenylphosphine) palladium dichloride and 0.3 g (8 mole %) of cuprous iodide were added. Reflux was continued another 11/2 hours before 1.0 ml (9.0 mmole) of phenylacetylene and 10 ml of triethylamine were added. After an additional 21/2 hours at reflux the reaction was partitioned between ether and water, washed with brine, dried over MgSO4 and evaporated in vacuo to yield 55 g of crude reaction product. The mixture was flash chromatographed eluting with 1:19 ethyl acetate: hexane to give 2.6 g (59%) of 2-(phenylethynyl)phenyl-2-propanone as a dark oil.

Provenance & Evidence