Synthesis of substituted 3-trifluoromethylbenzo[b]thiophenes

Tetrahedron Letters

Volumn 44, Issue 38, 2003, Pages 7147-7149

  Owton, W M ^a  

^a ELI LILLY AND COMPANY   (United States)

Author keywords

Lithiation; Trifluoromethylbenzothiophenes

Indexed keywords

ACETOPHENONE DERIVATIVE; THIOPHENE DERIVATIVE;

ARTICLE; CHEMICAL REACTION; PRECURSOR; SYNTHESIS; TECHNIQUE;

TRIFLUORO;

EID: 0042510242     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(03)01811-2     Document Type: Article

References (13)

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7. 4), filtered and concentrated under reduced pressure. The oily residue was passed through a pad of silica (eluent: hexane/ethyl acetate 5:1) to give methyl-3-trifluoromethylbenzothiophene-2-carboxylate as a yellow oil (66% yield).
8. Bridges A.J., Hammond A.L., Maduakor E.C., Schwartz C.E. Tetrahedron Lett. 33:1992;7495. and 7499.
9. Morita C., Hashimoto K., Okuno T., Shirahama H. Heterocycles. 52:2000;1163.
10. 4), filtered and concentrated under reduced pressure. The crude product was passed through a pad of silica (eluent: hexane/ethyl acetate, 4:1) to give 2-fluoro-5-chloro-2′2′2′-trifluoroacetophenone in 40% yield.
11. 4), filtered and concentrated under reduced pressure. The crude product was passed through a pad of silica (eluent: hexane/ethyl acetate, 19:1) to give 3-trifluoromethylbenzothiophene (1.92 g, 9. 5 mmol) in 75% yield.
12. CEM (Microwave Technology) Ltd, website: http://www.cemsynthesis.com.
13. 3BrS requires 279.9169, found 279.9160.