Place 5.6 g of KMnO 4 , 60 mL of water, 0.8 mL of 3 M NaOH, and 0.9 g of ethylbenzene in a 200 mL round bottom flask fitted with a reflux condenser. Add boiling chips and gently heat this mixture with occasional stirring at reflux for at least 2.5 hours. Severe bumping occurs if heated to strongly. Test the hot solution for unchanged permanganate by placing a drop of the reaction mixture on a piece of filter paper, if a purple ring appears around the brown spot of manganese dioxide, potassium permanganate remains. Destroy any excess ion by adding small amounts of sodium bisulfite until the spot test is negative. Avoid a large excess of bisulfite. Add ~1 g of filter aid (Celite) to the hot solution to aid in its rapid filtration. Filter by vacuum and rinse the reaction flask and filter cake with two small 5-7 mL portions of hot water. To increase the recovery of the crude product, concentrate the filtrate (reduce the total volume to about 15-20 mL) by boiling on a hot plate in a vent hood. (Don't forget to add
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This note was uploaded on 02/13/2011 for the course CHEM 2344 taught by Professor Slack,wu during the Spring '11 term at University of Houston.