(4-chlorophenyl)methanesulfonyl fluoride

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A catalytic amount (about 300 mg) of tetrabutylammonium bromide and 68 g of powdered anydrous potassium carbonate were added to a solution of 21.8 g 4-chlorophenylmethanesulphonyl fluoride and 23.3 g of 4-chlorophenacyl bromide in 200 ml of tetrahydrofuran at room temperature, while stirring. The mixture was stirred for a further 8 hours at 50° C. The reaction mixture was allowed to cool down to room temperature and was then filtered to remove inorganic substances which had precipitated. The organic phase was concentrated by stripping off the solvent under reduced pressure. The residue was recrystallized from ethanol. In this manner, 19.0 g of trans-1,3-di-(4-chlorophenyl)-prop-2-en-1-one were obtained in the form of yellow crystals of melting point 156° C. The mixture was stirred for a further 8 hours at 50° C was then filtered to remove inorganic substances which had precipitated The organic phase was concentrated The residue was recrystallized from ethanol