The Synthetic Routes of 4-CHLORO-1-METHYL-1H-PYRAZOLO[3,4-D]PYRIMIDINE

The synthesis of 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine is an important process in the chemical industry, as this compound is a key intermediate in the production of several pharmaceuticals and agrochemicals.
There are several synthetic routes that can be used to produce 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine, each with its own advantages and disadvantages.

One of the most common synthetic routes for 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine involves the reaction of methyl iodide with 4-chloro-3-methyl-1H-pyrazole-5-carboxylate in the presence of a base, such as sodium hydroxide.
The reaction proceeds through the intermediate formation of the carboxylic acid, which is then methylated with methyl iodide to form the desired product.

Another synthetic route involves the reaction of 4-chloro-1,3-dimethyl-1H-pyrazole-5-carboxylic acid with sodium hydroxide, followed by treatment with chloroform and sodium hypochlorite.
This route is less commonly used due to the potential hazards associated with the use of hypochlorite.

Yet another synthetic route for 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine involves the reaction of 4-chloro-3-methyl-1H-pyrazole-5-carboxylate with phenylboronic acid in the presence of a palladium catalyst and hydrogen gas.
This route is known as a Suzuki-Miyaura coupling reaction and is highly selective for the formation of the desired product.

Finally, 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine can also be synthesized through the reaction of 4-chloro-1,3-dimethyl-1H-pyrazole-5-carboxylic acid with 2,2'-dithio-bis(benzothiazole), followed by treatment with sodium hydroxide.
This route is also known as a Suzuki-Miyaura coupling reaction and is highly selective for the formation of the desired product.

In conclusion, the synthetic routes for 4-chloro-1-methyl-1H-pyrazolo[3,4-d]pyrimidine vary, but all involve the formation of the carboxylic acid intermediate, which is then transformed into the desired product through a variety of chemical reactions.
The choice of synthetic route depends on the specific requirements of the final product and the desired purity and yield.