- Equip a 100-ml round-bottomed two-necked flask with a magnetic follower bar, a dropping funnel and a thermometer positioned to dip into the reaction mixture.
- Site the flask in a plastic bowl on a magnetic stirrer unit.
- Place in the flask a solution of lg (0.0055 mol) of frans-l-ethynyl-3,3,5-trimethylcyclo-hexan-1-ol in 10 ml of acetone and add a solution of 1.25g (0.0079 mol) potassium permanganate in 25 ml of water from the dropping funnel with stirring over 1 hour.
- Ensure that the temperature of the reaction mixture is maintained below 20 °C by surrounding the reaction flask with ice-water.
- When the addition is complete, continue stirring at room temperature for 1 hour, and then heat the solution under reflux for a further hour.
- Cool the reaction mixture, filter, decolourise the filtrate by the passage of sulphur dioxide and acidify the solution with hydrochloric acid.
- The product obtained by filtration is dried in a vacuum desiccator before being recrystallised from light petroleum (b.p. 60-80 °C). The yield of pure product is 0.7g (58%);m.p. 134-135 °C.
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