The Production Process of 1-BENZYL-5,6-DIHYDROPYRIDIN-2(1H)-ONE

The production process of 1-benzyl-5,6-dihydropyridin-2(1H)-one, also known as benzylidenepyridine-2,5-dione, is a complex and multi-step process that involves various chemical reactions and purification steps.
This compound is commonly used in the pharmaceutical and agrochemical industries as an intermediate for the synthesis of various drugs and pesticides.

The production process of 1-benzyl-5,6-dihydropyridin-2(1H)-one can be broadly classified into the following steps:

1. Preparation of the starting materials: The production of 1-benzyl-5,6-dihydropyridin-2(1H)-one involves the use of several starting materials, such as benzaldehyde and acetonedicarboxylic acid.
   These starting materials are prepared through separate production processes, which involve the isolation and purification of the compounds from natural sources or their synthesis through chemical reactions.
   
2. Condensation reactions: The next step in the production process is the condensation of benzaldehyde and acetonedicarboxylic acid in the presence of a condensing agent, such as oxalic acid or dicyclohexylcarbonate.
   This reaction results in the formation of the diester of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one.
   
3. Hydrolysis: The diester of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one is then subjected to hydrolysis, which involves the cleavage of the ester group by a hydrolyzing agent, such as sodium hydroxide.
   This reaction results in the formation of the amide of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one.
   
4. Decarboxylation: The amide of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one is then subjected to decarboxylation, which involves the removal of the carboxylic acid group by a decarboxylating agent, such as sodium hydroxide or hydrochloric acid.
   This reaction results in the formation of the amine of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one.
   
5. Nitration: The amine of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one is then subjected to nitration, which involves the addition of nitrating agents, such as nitric acid or perchloric acid, to the amine.
   This reaction results in the formation of the nitro compound of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one.
   
6. Reduction: The nitro compound of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one is then subjected to reduction, which involves the removal of the nitro group by a reducing agent, such as lithium aluminum hydride or hydrogen in the presence of a catalyst.
   This reaction results in the formation of the amine of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one.
   
7. Halogenation: The amine of 1-benzyl-5,6-dihydro-pyridin-2(1H)-one is then subjected to halogenation, which involves the substitution of the amine group with a halogen atom.
   This can be achieved through the use of halogenating agents, such as phosphorus trichloride or thionyl chloride.
   This reaction results