Direct Incorporation of [11C]CO2 into Asymmetric [11C]Carbonates

Abstract

A novel carbon-11 radiolabelling methodology for the synthesis of the dialkylcarbonate functional group has been developed. The method uses cyclotron-produced short-lived [11C]CO2 (half-life 20.4 min) directly from the cyclotron target in a one-pot synthesis. Alcohol in the presence of base trapped [11C]CO2 efficiently forming an [11C]alkylcarbonate intermediate that subsequently reacted with an alkylchloride producing the di-substituted [11C]carbonate (34% radiochemical yield, determined by radio-HPLC) in 5 minutes from the end of [11C]CO2 cyclotron delivery.