The Synthetic Routes of 5-Iodo-3(2H)-pyridazinone

5-Iodo-3(2H)-pyridazinone is an important synthetic intermediate in the chemical industry, with a wide range of applications in the production of pharmaceuticals, agrochemicals, and other chemical products.
This compound can be synthesized through several different synthetic routes, each with its own advantages and disadvantages.

One of the most commonly used synthetic routes for the preparation of 5-iodo-3(2H)-pyridazinone is the iodination of 3-chloro-2-oxo-1,2-oxazolidine, which is accomplished by treating the chloride with iodine in the presence of a Lewis acid catalyst, such as aluminum chloride or ferric chloride.
This route is relatively simple and efficient, and allows for the formation of the iodo group in a highly regioselective manner.

Another synthetic route involves the reaction of 4-iodo-2,3-dihydro-1H-pyrazole with 2-aminomethyl-3-oxo-3H-pyraz-ol-4-carboxylic acid, in the presence of a coupling reagent, such as HATU or DCC.
This route is also highly efficient and allows for the formation of the iodo group in a highly regioselective manner.

The use of electrochemical methods for the synthesis of 5-iodo-3(2H)-pyridazinone has also been reported.
In this method, 3-chloro-2-oxo-1,2-oxazolidine is used as the starting material, and it is electrochemically reduced to form the corresponding amine, which is then iodinated using iodine and a Lewis acid catalyst.
This method is highly efficient and allows for the formation of the iodo group in a highly regioselective manner.

A more recent synthetic route involves the use of organocatalysts, such as 1,8-diazabicyclo[5.
4.
0]undec-7-ene or 2-oxindole, for the iodination of 3-chloro-2-oxo-1,2-oxazolidine.
This method is highly efficient and allows for the formation of the iodo group in a highly regioselective manner.

In conclusion, 5-iodo-3(2H)-pyridazinone is an important synthetic intermediate that can be synthesized through several different synthetic routes, each with its own advantages and disadvantages.
The choice of synthetic route depends on various factors, such as the availability of starting materials, the desired yield, and the desired product purity.
The synthetic routes described above are representative examples of the methods that are currently used in the chemical industry for the synthesis of 5-iodo-3(2H)-pyridazinone.