“…-8(7H)-one (16).-Into a two-necked flask fitted with a Dean-Stark trap and condenser were placed the diketone (4) (9.09 g, 38.5 mmol), etheylene glycol (9 1 ml), toluene-p-sulphonic acid monohydrate (480 mg, 2.5 mmol), and dry benzene (500 ml). The contents were refluxed to separate water, and the apparatus was replaced by a Soxhlet extractor containing a mixture of anhydrous calcium sulphate and molecular sieve 4 8, in a filter paper thimble.…”