Polyethylene glycol wrapped potassium bromide assisted chemical fixation of carbon dioxide

Polyethylene glycol (PEG 400) embedded potassium bromide i.e. [K ⁺{PEG}Br-] was found to be an extremely simple, highly efficient and recyclable promoter/medium for the cycloaddition reaction of epoxides and aziridines to CO₂ to give corresponding cyclic carbonates and oxazolidinones, respectively, under mild conditions without utilization of additional organic solvents or additive. The catalyst worked well for a wide variety of substrates and could be recovered easily and reused without significant loss of catalytic activity and selectivity.