The Synthetic Routes of Pinazepam

Pinazepam is a triazolopyridine derivative that is used as a short-acting hypnotic drug for the treatment of insomnia.
The molecule has a unique structure, which makes its synthesis a challenging task.
There are several synthetic routes available for the synthesis of pinazepam, some of which are outlined below.

1. Route 1: Synthesis of Pinazepam via the Condensation of N-Phenyl-N-(2-dimethylaminoethyl) acetamide and 2-(2-chlorophenyl) acetamide

This route involves the synthesis of N-phenyl-N-(2-dimethylaminoethyl) acetamide and 2-(2-chlorophenyl) acetamide, followed by their condensation to yield pinazepam.
The synthesis of N-phenyl-N-(2-dimethylaminoethyl) acetamide involves the reaction of N-(2-dimethylaminoethyl) acetamide with phenyl isocyanate in the presence of a base such as sodium hydroxide.
The synthesis of 2-(2-chlorophenyl) acetamide involves the reaction of 2-bromoaniline with acetyl chloride in the presence of a solvent such as dichloromethane.

2. Route 2: Synthesis of Pinazepam via the Coupling of 2-Chloro-6-nitroaniline and N-(2,6-dimethylphenyl) acetamide

This route involves the synthesis of 2-chloro-6-nitroaniline and N-(2,6-dimethylphenyl) acetamide, followed by their coupling to yield pinazepam.
The synthesis of 2-chloro-6-nitroaniline involves the reaction of 2,6-dichloroaniline with nitric acid in the presence of a solvent such as o-xylene.
The synthesis of N-(2,6-dimethylphenyl) acetamide involves the reaction of N,N-dimethylacetamide with 2,6-dimethylphenyl chloride in the presence of a base such as sodium hydroxide.

3. Route 3: Synthesis of Pinazepam via the Reduction of 2-(2-Chlorophenyl)-N-(2,6-dimethylphenyl) acetamide

This route involves the synthesis of 2-(2-chlorophenyl)-N-(2,6-dimethylphenyl) acetamide, followed by its reduction to yield pinazepam.
The synthesis of 2-(2-chlorophenyl)-N-(2,6-dimethylphenyl) acetamide involves the reaction of 2-bromo-6-nitroaniline with N,N-dimethylacetamide in the presence of a solvent such as dichloromethane.
The reduction of 2-(2-chlorophenyl)-N-(2,6-dimethylphenyl) acetamide can be achieved using hydrogen in the presence of a metal catalyst such as palladium on barium sulfate.

In conclusion, there are several synthetic routes available for the synthesis of pinazepam, each with its own advantages and disadvantages.
The choice of route depends on the availability of reagents, the cost of the synthesis, and the desired yield of the product.
The three routes outlined above are representative of the synthetic methods that have been reported in the literature for the synthesis of pinazepam.