DBU‐IL Catalyzed Aminolysis of Carbonates: Regioselective Carbamate Synthesis

ABSTRACT

A series of DBU‐derived ionic liquids (DBU‐ILs) were synthesized and evaluated as efficient, recyclable catalysts in the aminolysis of organic carbonates. The DBU cation, known for its strong basicity and nucleophilicity, was effectively combined with various counter anions to fine‐tune the catalytic performance and selectivity. The optimized DBU‐IL system promoted the aminolysis of cyclic carbonates (ethylene and propylene carbonates) under mild, solvent‐free conditions, affording the corresponding carbamates in high yields with excellent regioselectivity. The selectivity maximum achieved in the reaction of butylamine with EC was 90%, and 68% with PC. However, no alkylated products were found in these reactions, even at elevated temperatures. Mechanistic investigations suggested that the dual activation of both the amine and carbonate substrates by the DBU‐IL facilitated a concerted nucleophilic substitution pathway. The catalyst demonstrated remarkable stability and could be reused for multiple cycles without significant loss of activity. This protocol offers a green, efficient, and tunable approach for carbamate synthesis, highlighting the potential of DBU‐derived ILs as sustainable catalysts in such transformations and related synthetic applications.