Dimethyl Disulfide → 2-Fluoro-6-(methylsulfanyl)aniline

Temperature

-78 °C

A mixture of N-(t-butoxycarbonyl)-2-fluoroaniline (5.0 g, 24 mmoles) in anhydrous tetrahydrofuran (50 ml) was cooled to -78° C. under a nitrogen atmosphere. To this solution was added t-butyl lithium (2.0M, 57.6 mmoles, 28.8 ml) at such a rate that the temperature did not exceed -65° C. When the addition was complete, the mixture was stirred at -78° C. for an additional 15 minutes and at -20° C. for 2.5 hours. To this reaction mixture was added dimethyl disulfide (2.82 g, 30 mmoles) in 10 ml of anhydrous tetrahydrofuran while maintaining the temperature at -20° C. for an additional hour. The mixture was allowed to warm to ambient temperature and then 25 ml of 1N sodium hydroxide was added. The mixture obtained was extracted with diethyl ether (2×100 ml). The organic phase was separated and dried over magnesium sulfate and then the solvent was removed by evaporation under reduced pressure to obtain a tan solid. This was hydrolized in dilute hydrochloric acid (6N, 200 ml) by heating to reflux for three hours. The resulting solution was extracted with diethyl ether and the aqueous layer was neutralized with sodium hydroxide (6N, 200 ml), and extracted with methylene chloride, dried over magnesium sulfate and the solvent removed by evaporation under reduced pressure to obtain an amber oil. This was distilled to give 3.2 g (85% of theory) of the title compound, having a b.p. of 62°-65° C. at 0.2 mm Hg.

1. customdid not exceed -65° C
2. additionWhen the addition
3. temperaturewhile maintaining the temperature at -20° C. for an additional hour
4. temperatureto warm to ambient temperature
5. customThe mixture obtained
6. extractionwas extracted with diethyl ether (2×100 ml)
7. customThe organic phase was separated
8. dry with materialdried over magnesium sulfate
9. customthe solvent was removed by evaporation under reduced pressure
10. customto obtain a tan solid
11. temperatureby heating
12. temperatureto reflux for three hours
13. extractionThe resulting solution was extracted with diethyl ether
14. extractionextracted with methylene chloride
15. dry with materialdried over magnesium sulfate
16. customthe solvent removed by evaporation under reduced pressure
17. customto obtain an amber oil
18. distillationThis was distilled

ORD record

ord-465fcf1184bf4ecea8969fc9833f4180

Source dataset

uspto-grants-1989_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04818273