A combination of low xenon difluoride amount (56 mmol), dichloromethane as solvent and glass as vial material gave [18F]XeF2 in 22% RCY after 120 min (Table 1, entries 1–3), while an approximate doubling of the amount of xenon difluoride resulted in 79% RCY after only 60 min (Table 1, entries 4 and 5).