Reaktion #218803

Reaktionsgleichung

N-(2-fluorophenyl)-3,4-dimethoxythiobenzamide

sodium hydroxide

→

required product

Ausbeute 55.0%

4-Fluoro-2-(3,4-dimethoxyphenyl)benzothiazole

Ausbeute 55.0%

Lösungsmittel

water

ethanol

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled in an ice bath
2. 2
   FiltrationThe precipitate was collected by vacuum filtration
3. 3
   Waschenwashed with water
4. 4
   workup.DISSOLUTIONdissolved in ethyl acetate (10 mL)
5. 5
   Sonstigeinsoluble material was removed by filtration
6. 6
   EinengenThe filtrate was concentrated in vacuo
7. 7
   Sonstigethe crude product purified by column chromatography (dichloromethane)

Vorschrift

A solution of N-(2-fluorophenyl)-3,4-dimethoxythiobenzamide (0.850 g, 2.92 mmol) and sodium hydroxide (0.93 g, 23.3 mmol) in water (10 mL) and ethanol (0.5 mL) was added dropwise to a solution of potassium ferricyanide (3.84 g, 11.7 mmol) in water (5 mL) at 95° C. The resulting solution was stirred at 95° C. for a further 2 h and then cooled in an ice bath. The precipitate was collected by vacuum filtration, washed with water and dissolved in ethyl acetate (10 mL) and insoluble material was removed by filtration. The filtrate was concentrated in vacuo and the crude product purified by column chromatography (dichloromethane) to give the required product as a pale yellow powder (0.46 g, 55% yield), mp 129° C.; 1H NMR (DMSO-d6) δ 7.95 (1H, m, ArH), 7.65 (2H, m, ArH), 7.42 (2H, m, ArH), 7.15 (1H, m, ArH), 3.90 (3H, s, OMe), 3.88 (3H, s, OMe); m/z (CI) 290 (M++1); Anal. (C15H12FNO2S) C, H, N. C: found 62.36%, calc. 62.27%; H: found 4.19%, calc.4.18%; N: found 4.93%, calc. 4.84%.

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