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A synthesis of acetamidines
Jitendra R Harjani1, Chen Liang, Philip G Jessop
1Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
The Journal of Organic Chemistry
|February 15, 2011
Summary
A new method synthesizes pure acetamidines by reacting primary amines with N,N-dimethylacetamide dimethyl acetal. This approach suppresses unwanted imidate ester formation, crucial for compounds difficult to purify.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Primary amine condensation with N,N-dimethylacetamide dimethyl acetal typically yields both acetamidine and imidate ester.
- Product distribution is influenced by reaction temperature, solvent, and the primary amine's structure.
Purpose of the Study:
- To develop a selective synthesis method for pure acetamidines.
- To overcome purification challenges for specific acetamidine compounds.
Main Methods:
- Reaction of primary amines with N,N-dimethylacetamide dimethyl acetal.
- Addition of excess dimethylamine to suppress imidate ester formation.
- Optimization of reaction conditions (temperature, solvent).
Main Results:
- Exclusive formation of acetamidine achieved by using excess dimethylamine.
- Successful synthesis of pure acetamidines, including those not amenable to standard purification.
- Good yields of the target acetamidine products.
Conclusions:
- A novel and effective method for selective acetamidine synthesis is presented.
- This method is particularly valuable for preparing acetamidines that are difficult to purify via crystallization or distillation.
- The strategy offers a reliable route to high-purity acetamidines in good yields.
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