An efficient two-step method for the synthesis of 2-bromo-4-nitroimidazole, 6, a key building block for nitroimidazole drugs, has been developed. The synthesis involves dibromination of 4-nitroimidazole 10 followed by selective debromination using in situ reductive deiodination strategy. The reactions are facile, safe, and easy to scale up. The large-scale applicability of this improved method was tested by conducting the reactions on kilogram scale to produce the desired product in high yield and quality.
Pedada, S.R.; Satam, V.S.; Tambade, P.J.; Kandadai, S.A.; Hindupur, R.M.; Pati, H.N. An Improved Kilogram-Scale Synthesis of 2-Bromo-4-nitro-1H-imidazole: A Key Building Block of Nitroimidazole Drugs. Organic Process Research and Development (2013) 17 (9) 1149-1155. [DOI: 10.1021/op400095f]