Copper-Catalyzed Synthesis of Monosubstituted Carbodiimides from Aromatic Amines

Abstract

Carbodiimides, which contain the N=C=N group, are important intermediates in organic synthesis, especially for building nitrogen-containing heterocycles. Traditional methods often need harsh conditions, toxic cyanide sources, or costly catalysts, which limit their practicality. Here, we present a mild and efficient copper-catalyzed method for the direct synthesis of monosubstituted carbodiimides from aromatic amines, using malononitrile as a safe and accessible cyanide source. The reaction occurs under normal conditions, providing a cost-effective and environmentally friendly alternative to standard methods. This technique achieves high selectivity for monosubstituted carbodiimides with a wide range of substrates, marking a sustainable and practical progress in carbodiimide production. This reaction represents a significant advancement in synthetic organic chemistry since there have been no previous reports of the synthesis of monosubstituted carbodiimides in the literature.