Base-Catalyzed Highly Regioselective Synthesis of Bio-Based Hydroxyurethanes

The regioselective synthesis of carbamates from bio-derived cyclic carbonates and amines by using 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as an organocatalyst is reported. This methodology led to the preparation of a wide range of bio-sourced hydroxyurethanes from furan-, carvone- and limonene-based scaffolds under solvent-free and mild reaction conditions. Moreover, a comprehensive analysis of the process allowed us to optimize the catalyst loading with little or no impact on the process regioselectivity. New furan, carvone and limonene-based carbamates have been synthesized with high regioselectivity under solvent-free and mild reaction conditions. Moreover, a detailed study on the reaction conditions allowed for the drastic reduction of the TBD loading with almost no effect on the regioselectivity. image