Method for production of f-18 labeled amyloid beta ligands

A Method for producing a compound of Formula I

• comprising the steps of:
• Step 1:
• Radiolabeling compound of Formula II with a F-18 fluorinating agent, to obtain compound of Formula I, if R═H or to obtain compound of Formula III, if R=PG
• Step 2:
• If R=PG, cleavage of the protecting group PG to obtain a compound of Formula I,
• Step 3:
• Purification and Formulation of a compound of Formula I,
• wherein:
• n=1-6,
• X is selected from the group consisting of
• a) CH,
• b) N,
• R is selected from the group consisting of
• a) H,
• b) PG,
• PG is an “Amine-protecting group”,
• LG is a leaving group,
• wherein LG contains 0-3 fluorine atoms,
• wherein the radiofluorination reaction is carried out in acetonitrile, or in a mixture of acetonitrile and a co-solvent.