Reaktion #60983

Reaktionsgleichung

cesium carbonate

rac-2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl

tert-Butyl-1-piperazine carboxylate

1-Bromo-4-(trifluoromethoxy)benzene

→

title compound

Ausbeute 13.0%

4-(4-Trifluoromethoxy-phenyl)-piperazine-1-carboxylic acid tert-butyl ester

Ausbeute 13.0%

Lösungsmittel

toluene

ethylacetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was cool to room temperature
2. 2
   Filtrationfiltered
3. 3
   Sonstigethe solvent was removed in vacuo
4. 4
   SonstigeThe crude oil was chromatographed over silica gel

Vorschrift

To a mixture of cesium carbonate (1.88 g, 5.7 mmol), palladium(II)acetate (46.1 mg, 0.205 mmol), rac-2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl (192 mg, 0.31 mmol), tert-Butyl-1-piperazine carboxylate (928 mg, 4.93 mmol) and 1-Bromo-4-(trifluoromethoxy)benzene (1 g, 4.11 mmol) was added degazed toluene (10 ml). The mixture was heated to 100° C. for 4 hours. The mixture was cool to room temperature, diluted with ethylacetate, filtered and the solvent was removed in vacuo. The crude oil was chromatographed over silica gel: eluent: heptane/ethylacetate 0-10% over 20 minutes to provide the title compound (180 mg, 13%) as a yellow solid, MS (m/e): 347.4 (M+H, 100%).

Quelle