Significantly improved radiochemical yields in gaseous tritium reactions by iridium(i)-catalyzed hydrogen isotope exchange

Abstract

Hydrogen isotope exchange reactions with iridium(I) catalyst [(COD)Ir(IMes)(PPh₃)]X 2 with significantly increased (up to 7 fold) radiochemical yields (RCY) in tritium gas reactions are reported. To model the reactions the term of deuterium chemical yields (DCY) has been introduced. By reduction of the equivalents of deuterium or tritium gas used, by lowering gas pressures, we were able to increase the DCY or RCY up to 80% or 63%, respectively. This work contributes to our understanding and control of critical parameters in iridium catalysed HIE reactions to improve the key factors for RCY in future optimisations.