The Production Process of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester

The production process of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester is a complex and multi-step process that involves various chemical reactions and purification steps.
This article will provide a detailed overview of the production process of this compound, including the raw materials required, the various chemical reactions involved, and the purification steps needed to obtain pure 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester.

1. Raw Materials

The production of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester requires several raw materials, including 2-amino-5-trifluoromethylpyridine, acetic anhydride, and pyridine.
The use of high-quality raw materials is essential to ensure the quality and purity of the final product.

2. Chemical Reactions

The production of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester involves several chemical reactions, including the following:

(i) Condensation reaction between 2-amino-5-trifluoromethylpyridine and acetic anhydride in the presence of a condensation catalyst such as pyridine to form 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid.

(ii) Amide formation between 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid and ethyl bromide in the presence of a condensation catalyst such as Hunig's base to form 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester.

3. Purification Steps

The purification steps following the chemical reactions are critical to obtaining a pure sample of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester.
The following purification steps are typically used:

(i) Centrifugation: The mixture of reactants and products is centrifuged to separate the solid and liquid phases.
The solid phase can then be filtered and washed with solvents to remove any impurities.

(ii) Column chromatography: The mixture of reactants and products is passed through a column packed with an inert powder such as silica gel.
The different components of the mixture are separated based on their partitioning between the solid and liquid phases.
The desired product can be eluted from the column using a solvent that is eluted gradually, allowing for purification.

(iii) Recrystallization: The purified product is dissolved in a suitable solvent, and the solvent is slowly removed through evaporation.
The precipitated solid can then be collected and dried to obtain pure 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic acid ethyl ester.

4. Characterization of the Product

The final product is characterized using various analytical techniques, including the following:

(i) Infrared spectroscopy (IR): IR spectroscopy provides information about the functional groups present in the compound.
The IR spectrum of 1,2-Dihydro-2-oxo-6-(trifluoromethyl)-3-pyridinecarboxylic