Reaction #7076

Reaction equation

5-bromo-2-indolinone

3-nitrophenyl boronic acid

potassium carbonate

→

5-(3-Nitro-phenyl)-1,3-dihydro-indol-2-one

Yield 65.0%

Solvents

ethylene glycol dimethyl ether

water

Conditions

Workup

1. 1
   TemperatureThe reaction was heated
2. 2
   Temperatureto reflux overnight
3. 3
   Filtrationfiltered
4. 4
   workup.ADDITIONSaturated ammonium chloride was added
5. 5
   ExtractionThe water layer was extracted with ethyl acetate (3×20 mL)
6. 6
   DryingThe combined organic layer was dried with MgSO4
7. 7
   Filtrationfiltered
8. 8
   Othersolvent removed in vacuo
9. 9
   OtherThe product was purified by flash silica gel chromatography (3:2 hexane; ethyl acetate)

Procedure

5-bromo-2-indolinone (1.08 g, 5.09 mmol) and tetrakistriphenyl phosphine Pd (0) (0.273 g) were stirred under an atmosphere of nitrogen in ethylene glycol dimethyl ether (35 mL). After 15 minutes, 3-nitrophenyl boronic acid (1.70 g, 10.2 mmol) was added, followed by potassium carbonate (4.24 g, 30.7 mmol) in water (15 mL). The reaction was heated to reflux overnight, cooled to room temperature and then filtered. Saturated ammonium chloride was added. The water layer was extracted with ethyl acetate (3×20 mL). The combined organic layer was dried with MgSO4, filtered, and solvent removed in vacuo. The product was purified by flash silica gel chromatography (3:2 hexane; ethyl acetate) to give 5-(3-Nitro-phenyl)-1,3-dihydro-indol-2-one (0.084 g, 65%), Mp=269° C.; 1H NMR (DMSO) δ 10.5 (s, 1H), 8.38–8.36 (m, 1H) 8.17–8.14 (m, 1H), 8.10–8.07 (m, 1H), 7.75–7.60 (m, 3H), 6.95 (d, 1H, J=8.1 Hz), 3.57 (s, 2H); IR (KBr) 3420, 3190, 1700 cm−1; MS (EI) m/z 253 (M−H)−; CHN calculated for C14H10N2O: C, 66.14; H, 3.96; N, 11.02; Found: C, 64.59; H, 4.16; N, 9.43.

Source