Reaktion #477965

Reaktionsgleichung

tert-butyl 2-(benzofuran-2-carbonylamino)-4-(trifluoromethylsulfonyloxy)thiophene-3-carboxylate

sodium carbonate

ethanol

4-(trifluoromethoxy)phenylboronic acid

→

87

Ausbeute 25.0%

2-(benzofuran-2-carbonylamino)-4-[4-(trifluoromethoxy)phenyl]thiophene-3-carboxylic acid

Ausbeute 25.0%

Lösungsmittel

water

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Filtrationthe mixture was filtered through Celite
2. 2
   Waschenthe Celite rinsed with methylene chloride
3. 3
   WaschenThe organic fraction of the filtrate was washed with water
4. 4
   Trocknendried with sodium sulfate
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated
7. 7
   Sonstigepurified by preparative layer chromatography (10% ethyl acetate/Hexane)
8. 8
   workup.ADDITIONthen treated with a 1:1 mixture of methylene chloride and trifluoroacetic acid
9. 9
   EinengenAfter 4 hours the mixture was concentrated in vacuo
10. 10
    Sonstigethe residue triturated in methylene chloride
11. 11
    Sonstigedecanted
12. 12
    Sonstigedried under high vacuum

Vorschrift

tert-butyl 2-(benzofuran-2-carbonylamino)-4-(trifluoromethylsulfonyloxy)thiophene-3-carboxylate (85, 50 mg, 0.102 mmol), 4-(trifluoromethoxy)phenylboronic acid (32 mg, 0.153 mmol), Tetrakis(triphenylphosphine)palladium(0) (1.0 mg, 0.001 mmol), and sodium carbonate (42 mg, 0.407 mmol), were combined in 2:1:1 ethanol, toluene and water the biphasic mixture was stirred vigorously in sealed vial at 70 C. After 2 hours, the mixture was filtered through Celite and the Celite rinsed with methylene chloride. The organic fraction of the filtrate was washed with water, dried with sodium sulfate, filtered, concentrated, purified by preparative layer chromatography (10% ethyl acetate/Hexane) then treated with a 1:1 mixture of methylene chloride and trifluoroacetic acid. After 4 hours the mixture was concentrated in vacuo, and the residue triturated in methylene chloride, centrifuged, decanted and dried under high vacuum to give 87 as a white powder (11.1 mg, 25%). 1H NMR (500 MHz, DMSO d6) δ=13.35 (br, 1 H), 12.55 (br, 1 H), 7.87 (d, 1 H), 7.86 (s, 1 H), 7.76 (d, 1 H), 7.57 (t, 1 H), 7.49 (d, 2 H), 7.42 (t, 1 H), 7.36 (d 2 H), 7.08 (s, 1 H) ppm. ESI MS [M+H] 448.26.

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