Acetone → 1-(6-methyl-3,4-dihydro-2H-pyran-5-yl)ethan-1-one

Participants

Reaction Steps

A mixture of 130.4 g. (1.3 moles) of 2,4-pentanedione, 251.9 g. (1.6 moles) of 1,3-bromochloropropane, 168 g. (1.2 moles) of anhydrous potassium carbonate, 1 g. of anhydrous sodium iodide and 250 ml. of dry acetone is refluxed for 20 hours, under exclusion of humidity, with stirring. After cooling the mixture is filtered, washed with four 150-ml. portions of dry acetone, the combined acetone extract is evaporated, and the residue is subjected to fractionated distillation in vacuum, on a Vigreux column.

Provenance & Evidence