3,6-Dibromopyridazide

Grey yellow powder

3,6-dibromopyridazine is an important intermediate in organic synthesis. It is mainly used in pharmaceutical intermediates, organic synthesis, organic solvents, and can also be used in dye production, pesticide production and perfumery.

3,6-dibromopyridazine for Synthesis: A mixture of maleic hydrazide (1.1 g, 10 mmol) and PBr5 (4.7 g, 11 mmol) was heated at 100 °C until no more white fumes of hydrogen bromide were produced (~2 h). After cooling, the orange residue was poured into ice water and the resulting mixture was extracted with CH2Cl2 (3 x 20 mL). The organic layer was washed with saturated aqueous NaHCO3, dried over MgSO4, filtered and concentrated. The crude product was purified by flash column chromatography on silica gel (CH2Cl2) to give 3,6-dibromopyridazine as a white solid (1.20 g, 50%).