Efficient Preparation of 5-Amino-4-cyano-N-(cyclopropylcarbamoyl)-3-aryl-2,3-dihydrothiophene-2-carboxamide Derivatives Without Using Any Other Catalysts

Abstract

An efficient synthesis of 5-amino-4-cyano-N-(cyclopropylcarbamoyl)-3-aryl-2,3-dihydrothiophene-2-carboxamide derivatives by the reaction of thiazolidine-2,4-dione, aromatic aldehydes, malononitrile, and cyclopropylamine has been reported. This reaction could be carried out smoothly without using any other catalysts in anhydrous ethanol. The advantages of this procure were good yields, short reaction time, and mild reaction conditions. Moreover, the purification process of products was very simple. The products could be gained only as the reactants were cooled under room temperature, and the precipitate could be brought out. These precipitate only need to filter out, without further purification.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

GRAPHICAL ABSTRACT

Keywords:

• Cyclopropylamine
• 2,3-dihydrothiophene
• multicomponent reactions
• synthesis
• thiazolidine-2,4-dione

ACKNOWLEDGMENTS

We are grateful to the National Natural Science Foundation of China (NSFC) (21172188), the Foundation of Xuzhou Normal University (10XLS02), and the Priority Academic Program Development of Jiangsu Higher Education Institutions for financial support.

Notes

Note. Reagents and conditions: thiazolidine-2,4-dione (1 mmol), 4-chlorobenzaldehyde (1 mmol), malononitrile (1 mmol), cyclopropylamine (1.2 mmol), and EtOH (8 mL).

^a Unless explicitly stated, the reaction was conducted under reflux conditions.

^b Isolated products.