Ethyl Bromide → (3-Bromo-5-(trifluoromethyl)phenyl)(ethyl)sulfane

Dithiocarbonic acid S-(3-bromo-5-trifluoromethyl-phenyl)ester O-ethyl ester (3.3 g, 10.3 mmoles) was dissolved into 30 mL of EtOH, 10 mL of H2O, and was sealed under nitrogen. To this stirring mixture was added KOH (2.8 g, 50 mmoles) and this mix was stirred at reflux (under nitrogen) for 12 hours. After this period the reaction mixture was evaporated in vacuo and combined with 50 mL of water. The pH was adjusted to <2 using 6N HCl and the resulting mixture was extracted with diethyl ether (3×50 mL). The combined ethereal layer was washed with brine and dried over anhydrous MgSO4. Following evaporation in vacuo the crude thiol was dissolved into 50 mL of acetone. Ethyl bromide (1.5 mL, 20.1 mmoles) and K2CO3 (5 g, 36.2 mmoles) were added, and the mixture was stirring at ambient temperature (under nitrogen) for 6 hours. After this period the mixture was gravity filtered, and evaporated in vacuo to yield crude product. The crude product was purified using flash silica chromatography (0-1% EtOAc/Hexane) to yield 1-bromo-3-ethylsulfanyl-5-trifluoromethyl-benzene (1.33 g, 45% yield) as a yellowish liquid. 1H-NMR (CDCl3): δ 7.56 (s, 1H), 7.52 (s, 1H), 7.43 (s, 1H), 3.0 (q, J=7.3 Hz, 2H), 1.36 (t, J=7.3 Hz, 3H).

1. customwas sealed under nitrogen
2. temperatureat reflux (under nitrogen) for 12 hours
3. customAfter this period the reaction mixture was evaporated in vacuo
4. extractionthe resulting mixture was extracted with diethyl ether (3×50 mL)
5. washThe combined ethereal layer was washed with brine
6. dry with materialdried over anhydrous MgSO4
7. customevaporation in vacuo the crude thiol
8. dissolutionwas dissolved into 50 mL of acetone
9. stirringthe mixture was stirring at ambient temperature (under nitrogen) for 6 hours
10. waitAfter this period the mixture was
11. filtrationgravity filtered
12. customevaporated in vacuo
13. customto yield crude product
14. customThe crude product was purified

ORD-Eintrag

ord-3c8cf34acaf14531a22f47a8e7c11a43

Quelldatensatz

uspto-grants-2009_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07482366B2