The Production Process of 4-Pyridazinecarboxylic acid, 6-chloro-, methyl ester

The production process of 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester is a complex and multi-step process that involves several chemical reactions and purification steps.
The following is an overview of the production process of 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester.

Step 1: Preparation of 4-amino-2-chloropyridine
The production of 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester begins with the preparation of 4-amino-2-chloropyridine, which is a key intermediate in the production process.
This intermediate is typically prepared by reacting 2-chloropyridine with sodium azide in the presence of a solvent such as water or acetonitrile.

Step 2: Condensation of 4-amino-2-chloropyridine with Pyridine-2,5-dicarboxylic acid
The next step in the production process is the condensation of 4-amino-2-chloropyridine with pyridine-2,5-dicarboxylic acid.
This condensation reaction is typically carried out in the presence of a solvent such as acetonitrile or ether, and is often catalyzed by a strong acid catalyst such as sulfuric acid.

Step 3: Esterification of 4-amino-2-chloropyridine with Methanol
The resulting product from the condensation reaction is then subjected to esterification with methanol to form 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester.
This esterification reaction is typically carried out in the presence of a solvent such as water or methanol, and is often catalyzed by a strong acid catalyst such as sulfuric acid or phosphoric acid.

Step 4: Purification of the Product
After the esterification reaction is complete, the resulting product is typically purified by several purification steps.
The first step is typically a removal of the solvent, then the product is typically dissolved in a solvent such as ethyl acetate or dichloromethane, and then the mixture is passed through a column containing an inert solid such as silica gel or alumina.
The resulting pure product is then collected and dried.

The final product is a white or slightly yellowish solid that is soluble in organic solvents such as ethanol, acetonitrile, and ether.

In conclusion, the production process of 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester is a multi-step process that involves several chemical reactions and purification steps.
The key intermediate, 4-amino-2-chloropyridine, is typically prepared by reacting 2-chloropyridine with sodium azide in the presence of a solvent such as water or acetonitrile.
The condensation of 4-amino-2-chloropyridine with pyridine-2,5-dicarboxylic acid, followed by esterification with methanol, results in the formation of 4-pyridazinecarboxylic acid, 6-chloro-, methyl ester.
The final product is a white or slightly yellowish solid that is soluble in organic solvents such as ethanol, acetonitrile, and ether.