The multistep preparation of C-11-levetiracetam ((CLEV)-C-11) was carried out by a one-pot radiosynthesis with 8.3 +/- 1.6% (n = 8) radiochemical yield in 50 +/- 5.0 min. Briefly, the propionaldehyde was converted to propan-l-imine in situ as labeling precursor by incubation with ammonia. Without further separation, the imine was reacted with C-11-HCN to form C-11-aminonitrile. This crude was then reacted with 4-chlorobutyryl chloride and followed by hydrolysis to yield C-11-LEV after purification by chiral high-performance liquid chromatography (HPLC). Both the radiochemical and enantiomeric purities of C-11-LEV were >98%.