Reaktion #64163

Reaktionsgleichung

4-phenylsulfonylphenylethyne

n-BuLi

1,1,1-trifluoroacetone

→

butyne

Ausbeute 75.3%

4,4,4-Trifluoro-3-hydroxy-3-methyl-1-(4-phenylsulfonylphenyl)but-1-yne

Ausbeute 75.3%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   Sonstigebefore quenching with 2N HCl
3. 3
   workup.ADDITIONDiethyl ether was added
4. 4
   Extraktionthe aqueous layer extracted further with diethyl ether
5. 5
   SonstigeThe combined organic layers were dried
6. 6
   Sonstigeevaporated
7. 7
   Sonstigethe product purified by chromatography, with ethyl acetate

Vorschrift

To a cooled (-78° C.) solution of 4-phenylsulfonylphenylethyne (66 mg, 0.27 mmol) in freshly distilled tetrahydrofuran (2.5 mL) was added n-BuLi (109 mL, 2.5M solution in hexanes, 0.27 mmol). The solution was stirred for 10 minutes at -78° C. at which time 1,1,1-trifluoroacetone (272 mL, 1.0M solution in tetrahydrofuran, 0.27 mmol) was added. The reaction mixture was kept at -78° C. for five minutes before quenching with 2N HCl . Diethyl ether was added, and the aqueous layer extracted further with diethyl ether. The combined organic layers were dried, evaporated and the product purified by chromatography, with ethyl acetate:hexanes as eluent (1:4) to yield the title butyne as a white solid (72 mg, 75%); mp 94.8°-95.3° C.; 250 MHz NMR (CDCl3): 1.72 (s,3, CH3), 3.08 (s,1, OH), 7.48-7.60 (m,5, Ar), 7.87-7.94 (m,4, Ar); MS: m/z=355(M+ 1). Analysis for C17H13F3O3S: Calculated: C, 57.62; H, 3.70; Found: C, 57.46; H, 3.65.

Quelle