Reaction #302848

Reaction equation

Tin(II) chloride

compound 4

6-bromo-4′-nitroflavone

sodium hydroxide

→

compound 5

6-bromo-4′-aminoflavone

Solvents

ethanol

Conditions

Workup

1. 1
   TemperatureThe obtained mixture was heated
2. 2
   Temperatureto reflux for 1 hour
3. 3
   OtherAfter completion of the reaction
4. 4
   Extractionthe obtained mixture was then extracted with 50 ml (25 ml×2) of ethyl acetate
5. 5
   DryingThe extract was dried over anhydrous sodium sulfate
6. 6
   workup.DISTILLATIONthe solvent was then distilled away under reduced pressure

Procedure

Tin(II) chloride (275 mg, 1.45 mmol) was slowly added to an ethanol solution (7 ml) that contained compound 4 (100 mg, 0.289 mmol), while stirring. The obtained mixture was heated to reflux for 1 hour. After completion of the reaction, a 1 N sodium hydroxide aqueous solution (50 ml) was added to the reaction solution, and the obtained mixture was then extracted with 50 ml (25 ml×2) of ethyl acetate. The extract was dried over anhydrous sodium sulfate, and the solvent was then distilled away under reduced pressure, so as to obtain a product of interest, 6-bromo-4′-aminoflavone (compound 5) in the form of a yellow crystal. Yield: 77 mg (yield constant: 84.3%) 1H NMR (300 MHz, CDCl3) δ8.36 (s, 1H), 7.72-7.76 (m, 3H), 7.44 (d, J=9.0 Hz, 1H), 6.72 (d, J=8.7 Hz, 2H), 6.70 (s, 1H), 4.15 (s, 2H). MS m/z 317 (MH+).

Source