反应详情

16.5 g (0.1 mol) of 3-bromo-3-methyl-2-butanone and 11.6 g (0.12 mol) of potassium rhodanide in 150 ml of anhydrous acetone are heated at reflux for about 11/2 hours. After cooling, the separated potassium bromide is filtered off under suction and backwashed with a small amount of acetone, and the filtrate is evaporated to dryness at 50° C. under reduced pressure. The residue is dissolved in 200 ml of diethyl ether and the solution is washed three times with 100 ml of water each time, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure.The crude product is fractionated on a short Vigreux column to yield 3-methyl-3-thiocyanato-2-butanone, b.p. 52° C./0.04 mmHg.

1. temperatureat reflux for about 11/2 hours
2. temperatureAfter cooling
3. filtrationthe separated potassium bromide is filtered off under suction
4. customthe filtrate is evaporated to dryness at 50° C. under reduced pressure
5. dissolutionThe residue is dissolved in 200 ml of diethyl ether
6. washthe solution is washed three times with 100 ml of water each time
7. dry with materialdried over anhydrous sodium sulfate
8. customevaporated to dryness under reduced pressure