Reaction #7077

Reaction equation

sodium carbonate

bromine

3-methyl-2-indolinone

sodium acetate

→

title compound

Yield 93.7%

5-bromo-3-methyl-indol-2-one

Yield 93.7%

Solvents

acetic acid

acetic acid

Conditions

Workup

1. 1
   Otherto quench
2. 2
   Otherthe reaction
3. 3
   ExtractionThe water layer was extracted with EtOAc (×3)
4. 4
   Dryingdried (MgSO4)
5. 5
   Filtrationfiltered
6. 6
   Otherevaporated

Procedure

Under an atmosphere of nitrogen, bromine (0.96 g, 6.0 mmol) in acetic acid (5 cm3) was added drop wise to a solution of 3-methyl-2-indolinone (0.8749 g, 6.0 mmol) (Kende, et al, Synth. Commun., 12, 1, 1982) and sodium acetate (0.50 g, 6.0 mmol) in acetic acid (10 cm3). The reaction was stirred at room temperature for 3.5 h. Saturated sodium carbonate was added to quench the reaction. The water layer was extracted with EtOAc (×3), dried (MgSO4), filtered, and evaporated to give the title compound (1.26 g, 93%), Mp=119–120° C.; 1H NMR (DMSO) δ 1.32 (d, 3H, J=7.66 Hz), 3.45 (q, 1H, J=7.62 Hz), 6.77 (d, 1H, J=8.23 Hz), 7.46 (s, 1H), 7.36–7.33 (m, 1H), 10.4 (s, 1H); IR (KBr) 3200, 1725 cm−1; MS (EI) m/z 224/226 (M−H)−; CHN calculated for C9H8BrNO: C, 47.82; H, 3.57; N, 6.20; Found: C, 47.44; H, 3.42; N, 6.04.

Source