Boric Acid → p-Phenylpropiophenone

Participants

Reaction Steps

A mixture containing phenylboric acid (6.1 g; 50 mmol), 4′-bromopropiophenone (10.65 g; 50 mmol), sodium carbonate (5.3 g; 50 mmol) and palladium chloride (500 mg, 2.8 mmol) in 300 ml of water is heated under reflux for 4 hours. Boric acid (1 g; 0.8 mmol) is then added followed by heating for 30 minutes. Once the mixture has been returned to 23° C., 250 ml of ethyl acetate is added followed by filtering on frit then on GFA paper. The filtrate is decanted and the organic phase is washed with a saturated solution of NaCl before being dried over MgSO4 and concentrated using a rotary evaporator. The precipitate is stirred for 30 minutes in 100 ml of isopentane and 5 ml of dichloromethane. After filtration on frit, the solid is rinsed with isopentane. A cream coloured powder is obtained (8.7 g; 83%). Melting point: 98-99° C. MH+=211.1

Provenance & Evidence