High yield synthesis of 6-[18F]fluoro-L-dopa.

The radiofluorination of L-dopa with [18F]F2 was investigated with the purpose of improving the yield of 6-[18F]fluoro-L-dopa. When boron trifluoride was added to the reaction mixture in hydrogen fluoride (HF), the yield was increased threefold. Nine millicuries of 6-[18F]fluoro-L-dopa were produced from 100 mCi [18F]F2 routinely and reliably after 2 hr of preparation. If acetonitrile or water were substituted for HF, little or no 6-fluoro-L-dopa was made.