反应详情

3.71 g (33.1 mmol) of potassium tert-butoxide were added to a solution of 4.00 g (15.0 mmol) of 2-methoxy-3-(methylsulfanyl)-4-(trifluoromethyl)benzoic acid in 250 ml of methanol. The mixture was stirred for 10 minutes, and 1.07 g (25.5 mmol) of cyanamide and 4.81 g (27.0 mmol) of N-bromosuccinimide were then added in succession. The contents were then stirred at RT for 2 h. The mixture was then freed from the solvent on a rotary evaporator and the residue was taken up in a mixture of in each case 120 ml of acetonitrile and water. 7.21 g (45.1 mmol) of sodium permanganate monohydrate were added, and the mixture was stirred at RT for one week. During this week, both after one day and after a further day, in each case 3.6 g (22.5 mmol) of sodium permanganate monohydrate were added. For work-up, a 10% by weight strength solution of sodium bisulfate was added. On a rotary evaporator, at a temperature of at most 30° C., the solvent was substantially removed. The residue was cooled in an ice bath and then acidified with 1M hydrochloric acid. The mixture was extracted three times with ice-cold dichloromethane. The combined organic phases were freed from the solvent on a rotary evaporator and the residue was purified chromatographically, which gave 1.30 g of product of a purity of 80% by weight.

1. stirringThe contents were then stirred at RT for 2 h
2. customThe mixture was then freed from the solvent on a rotary evaporator
3. additionthe residue was taken up in a mixture of in each case 120 ml of acetonitrile and water
4. stirringthe mixture was stirred at RT for one week
5. waitDuring this week
6. waitafter one day
7. waitafter a further day
8. customOn a rotary evaporator
9. customat a temperature of at most 30° C., the solvent was substantially removed
10. temperatureThe residue was cooled in an ice bath
11. extractionThe mixture was extracted three times with ice-cold dichloromethane
12. customThe combined organic phases were freed from the solvent on a rotary evaporator
13. customthe residue was purified chromatographically