Potassium Carbonate → HCID 59133208, compound

Temperature

45 °C

To a stirred solution of 2-(trifluoromethyl)benzenethiol (5.000 g, 0.028 mol) in acetone (50 mL) was added 2-bromo-1,1-diethoxyethane (6.08 g, 0.030 mol) and potassium carbonate (7.757 g, 0.056 mol). The resulting mixture was then stirred at 45° C. for 2 hours prior to removal of the solvent in vacuo and suspension of the residue in EtOAC. The inorganic salts were filtered off and the organic phase was concentrated to give crude product, which was used in next step without further purification. This residue was dissolved in toluene (50 mL), and to this solution was added PPA (10 g) and the resulting mixture stirred at 95-100° C. for 2 hours. The mixture was allowed to cool to rt, was poured into ice-water, then extracted with EtOAc (3×50 mL). The combined extracts were washed with aqueous sodium bicarbonate followed by brine, then dried over anhydrous sodium sulfate and evaporated under reduced pressure to yield an oil. This was purified by column chromatography over silica gel eluting with hexane to give 7-trifluoromethyl-benzo[b]thiophene. 1H NMR (400 MHz, MeOD) δ ppm 7.49-7.57 (m, 2H), 7.70 (d, J=7.33 Hz, 1H), 7.74 (d, J=5.56 Hz, 1H) and 8.10 (d, J=8.08 Hz, 1H).

1. customto removal of the solvent
2. additionin vacuo and suspension of the residue in EtOAC
3. filtrationThe inorganic salts were filtered off
4. concentrationthe organic phase was concentrated
5. customto give crude product, which
6. customwas used in next step without further purification
7. dissolutionThis residue was dissolved in toluene (50 mL)
8. additionto this solution was added PPA (10 g)
9. stirringthe resulting mixture stirred at 95-100° C. for 2 hours
10. temperatureto cool to rt
11. additionwas poured into ice-water
12. extractionextracted with EtOAc (3×50 mL)
13. washThe combined extracts were washed with aqueous sodium bicarbonate
14. dry with materialdried over anhydrous sodium sulfate
15. customevaporated under reduced pressure
16. customto yield an oil
17. customThis was purified by column chromatography over silica gel eluting with hexane

ORD record

ord-9dc6a36fc29149d28ce0576740642bc4

Source dataset

uspto-grants-2010_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07700594B2