The Production Process of 5-Iodo-3(2H)-pyridazinone

5-Iodo-3(2H)-pyridazinone is an organic compound that is commonly used as a building block in the production of various chemicals and pharmaceuticals.
The production process of 5-Iodo-3(2H)-pyridazinone involves several steps, which are outlined below.

1. Synthesis of 2-bromo-3-nitropyridine
   The first step in the production of 5-Iodo-3(2H)-pyridazinone is the synthesis of 2-bromo-3-nitropyridine.
   This compound is synthesized by treating 2-bromo-3-aminopyridine with nitrous acid.
   The reaction is exothermic and requires careful monitoring to avoid excessive heating.
   
2. Reduction of 2-bromo-3-nitropyridine to 2-bromo-3-nitropyridane
   Next, the 2-bromo-3-nitropyridine is reduced to 2-bromo-3-nitropyridane using a reducing agent such as lithium aluminum hydride (LiAlH4).
   This step is necessary to reduce the nitro group to an amino group.
   
3. Condensation of 2-bromo-3-nitropyridane with Malonic acid
   In the next step, the 2-bromo-3-nitropyridane is condensed with malonic acid in the presence of a condensing agent such as dicyclohexylcarbodiimide (DCC).
   This reaction results in the formation of a diester, which is then hydrolyzed using sodium hydroxide to yield 3-bromo-2-pyridinecarboxylic acid.
   
4. Nitration of 3-bromo-2-pyridinecarboxylic acid
   The 3-bromo-2-pyridinecarboxylic acid is then nitrated using nitric acid to yield 3-bromo-2-pyridinecarboxylic acid nitrate.
   
5. Reduction of 3-bromo-2-pyridinecarboxylic acid nitrate to 3-bromo-2-pyridinecarboxylic acid
   The 3-bromo-2-pyridinecarboxylic acid nitrate is reduced to 3-bromo-2-pyridinecarboxylic acid using a reducing agent such as lithium aluminum hydride (LiAlH4).
   
6. Halogenation of 3-bromo-2-pyridinecarboxylic acid
   The 3-bromo-2-pyridinecarboxylic acid is then halogenated using Iodine and a solvent such as carbon tetrachloride.
   This step results in the formation of 3-bromo-5-iodo-2-pyridinecarboxylic acid.
   
7. Dehydration of 3-bromo-5-iodo-2-pyridinecarboxylic acid
   The next step is to remove water from the 3-bromo-5-iodo-2-pyridinecarboxylic acid using a dehydrating agent such as phosphorus trichloride.
   This step is necessary to prevent the formation of unwanted side products during the subsequent steps.
   
8. Reduction of 3-bromo-5-iodo-2-pyridinecarboxylic acid to 5-iodo-3(2H)-pyridazinone
   Finally, the 3-bromo-5-iodo-2-pyridinecarboxylic acid is reduced to 5-iodo-3(2H)-pyridazinone using a reducing agent such as lithium aluminum hydride (LiAlH4).
   This step requires careful