The Synthetic Routes of 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine

3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine is an important intermediate in the synthesis of several pharmaceuticals, agrochemicals, and other industrial chemicals.
The efficient and cost-effective synthesis of this compound is of great interest to the chemical industry.
There are several synthetic routes available for the synthesis of 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine, and in this article, we will discuss some of the most commonly used methods.

One of the most popular methods for the synthesis of 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine is the route that involves the reaction of 4-chloro-6-nitro-1,2,3,6-tetrazine with 1-methyl-1H-pyrazole in the presence of a Lewis acid catalyst.
This method involves a multi-step synthesis, where the 4-chloro-6-nitro-1,2,3,6-tetrazine is first synthesized from guanidine and nitric acid, and then reacted with 1-methyl-1H-pyrazole in the presence of a Lewis acid catalyst such as AlCl3 or BF3.
The reaction is typically carried out in an inert solvent such as dichloromethane or chloroform, and the product is isolated by precipitation with a polar solvent such as ice-cold water.

Another synthetic route for 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine involves the reaction of 4-chloro-6-methyl-1,2,3,6-tetrahydropyridazine with 1-methyl-1H-pyrazole in the presence of a strong base such as sodium hydroxide.
This method involves a one-pot reaction, where the 4-chloro-6-methyl-1,2,3,6-tetrahydropyridazine is first synthesized from 4-chloro-1,2,3,6-tetrahydropyridine and methylamine, and then reacted with 1-methyl-1H-pyrazole in the presence of sodium hydroxide.
The reaction is typically carried out in an aqueous medium, and the product is isolated by filtration and washing with water.

A third synthetic route for 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine involves the reaction of 2-chloro-5-cyanopyridine with 1-methyl-1H-pyrazole in the presence of a metal catalyst such as RuCl2 or Pd(OAc)2.
This method involves a one-pot reaction, where the 2-chloro-5-cyanopyridine is first synthesized from chloramine and 2-cyanopyridine, and then reacted with 1-methyl-1H-pyrazole in the presence of the metal catalyst.
The reaction is typically carried out in an inert solvent such as toluene, and the product is isolated by filtration and washing with a solvent such as ethyl acetate.

In conclusion, there are several synthetic routes available for the synthesis of 3-chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine, and each method has its own advantages and disadvantages.
The choice of synthetic route depends on various factors, such as the availability of starting materials, the scalability of the process, and the cost and environmental impact of