Sodium Sulfate → 1-(3,4-Dihydroxy-5-nitrophenyl)ethanone

Reaction equation

[OH:1][C:2]1[C:7]([N+:8]([O-:10])=[O:9])=[CH:6][C:5]([C:11](=[O:13])[CH3:12])=[CH:4][C:3]=1[O:14]C.S([O-])([O-])(=O)=O.[Na+].[Na+]>C(O)(=O)C.Br>[OH:14][C:3]1[CH:4]=[C:5]([C:11](=[O:13])[CH3:12])[CH:6]=[C:7]([N+:8]([O-:10])=[O:9])[C:2]=1[OH:1]

Participants

Procedure

A solution containing 19.9 g of the product obtained in Example 18 in 200 ml of acetic acid and 200 ml of 48% hydrobromic acid was refluxed for 5 h. 500 ml of a saturated solution of sodium sulfate was added to the reaction mixture and the same was let stand overnight at 5° C. The solution was extracted with ether. The ether phase was washed with 200 ml of water, dried and the solvent evaporated in vacuo. The residue was crystallized from isopropanol. Yield 10.2 g (55 m.p. 155°-159° C.