Reaction #640517

Reaction equation

4-[1-(4-bromophenacyl)-1H-benzimidazol-2-yl]-furazan-3-ylamine

sodium bicarbonate

hydroxylamine hydrochloride

→

title compound

4-[1-(4-Bromophenacyl)-1H-benzimidazol-2-yl]-furazan-3-ylamine oxime

Solvents

ethanol

Conditions

Workup

1. 1
   Temperatureis refluxed for 20 hours
2. 2
   OtherPartitioning of the reaction mixture between ethyl acetate and water, separation of the organic phase
3. 3
   Otherby drying
4. 4
   Otherevaporation of the solvent
5. 5
   Othergives the crude product
6. 6
   OtherPurification by chromatography on silicagel

Procedure

A mixture of 4-[1-(4-bromophenacyl)-1H-benzimidazol-2-yl]-furazan-3-ylamine (0.083 g, 0.21 mmol, prepared according to Example 1), sodium bicarbonate (0.021 g, 0.25 mmol) and hydroxylamine hydrochloride (0.014 g, 0.21 mmol) in ethanol (5 ml) is refluxed for 20 hours. Partitioning of the reaction mixture between ethyl acetate and water, separation of the organic phase followed by drying and evaporation of the solvent gives the crude product. Purification by chromatography on silicagel yields the title compound as an E/Z-mixture, m.p. 198-201° C.

Source