N-Formylation of Secondary Amines and Their Application in the Synthesis of Benzimidazole Derivatives Using DMF as a C1 Source

Numerous methodologies for the N-formylation of amines using DMF as a formylating agent often require harsh conditions. Meanwhile, the synthesis of benzimidazole derivatives using DMF as a C1 source remains underexplored, with most methods relying on high temperatures and metal catalysts. In this study, we present a highly efficient N-formylation of amines at room temperature within 5 min utilizing the Vilsmeier reagent. Furthermore, we demonstrate its applicability in the synthesis of benzimidazole derivatives under milder conditions employing DMF as the C1 source.