Sulfuric Acid → 1,3-dibromo-5-nitrobenzene

Participants

Reaction Conditions

Reaction Steps

To a stirred, boiling (90° C.) mixture of 2,6-dibromo-4-nitroaniline (1 g, 3.38 mmol), ethanol (12 mL) and concentrated sulfuric acid (2 mL), sodium nitrite (0.75 g, 10.88 mmol) was added in portions as rapidly as foaming would permit. The reaction mixture was stirred at 90° C. for 30 h. The mixture was allowed to cool, poured into ice water and the solids were collected by filtration and washed with water. The 3,5-dibromobenzene was separated from the remaining inorganic salts by dissolving it in boiling ethanol and filtering the hot solution, from which 0.457 g (47% yield) of the product (30) crystallized on cooling: 1H-NMR (400 MHz, CDCl3) δ 8.32 (d, J=1.6 Hz, 2 H), 8.00 (t, J=1.6 Hz, 1 H).

Provenance & Evidence