DBU as activator for the N-iodosuccinimide promoted chemical fixation of carbon dioxide with epoxides

The combination of N-Iodosuccinimide (NIS) and DBU is developed as an efficient organocatalyst system for the cycloaddition of carbon dioxide (CO2) at atmospheric pressure with epoxides without utilization of additional solvents, forming cyclic carbonates in high yields with a broad substrate scope. DBU functions as a nucleophilic promoter for the activation of NIS to be a more electrophilic iodine species thus being capable of activating the epoxides. On the other hand, NIS also provides a nucleophilic nitrogen species, i.e. succinimide anion for ring-opening of the epoxide. (C) 2017 Elsevier Ltd. All rights reserved.