Reaktion #496

Reaktionsgleichung

Brc1ccccc1

Nc1ccc(S(N)(=O)=O)cc

→

NS(=O)(=O)c1ccc(Nc2c

Ausbeute 30.0%

Lösungsmittel

CC(=O)N(C)C

Reaktionsbedingungen

Vorschrift

A mixture of 4-aminobenzenesulfonamide (100 mg, 0.58 mmol), bromobenzene (0.061 mL, 0.58 mmol),(9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (26.9 mg, 0.05 mmol), diacetoxypalladium (5.21 mg, 0.02 mmol) and cesium carbonate (227 mg, 0.70 mmol) in degassed DMA (1.8 mL) was heated **_in the microwave_** for 20 min at 130 °C. LC MS FLA-04227-96-01 (pH extract 7-8) showed some product and a few bromobenzene left. Heating was continued for 15 min at 150°C. LC MS FLA-04227-96-02 (pH extract 7-8) showed reaction stalled. Reaction was stopped. Extraction with AE + ethanol / aq. sat NH4Cl (pH7), then back extraction with DCM.The organics were dried over MgSO4 and concentrated _in vacuo._ The crude product was adsorbed on silica gel 40-60µm and purified by flash chromatography on silica gel 15-40µm eluting with 2 % of ethanol in dichloromethane (NH3 0.5 %) to provide 4-(phenylamino)benzenesulfonamide (60.0 mg, 41.6 %) as a gum. 1H NMR, LC MS FLA-04227-96-03: OK **_Note: the product still contains 24% mol DMA_** **_Corrected yield: 30%_**

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