Patent ID: 8895727

Claim:
A method for preparing fluorine-18-labeled flumazenil, comprising reacting a diaryliodonium salt precursor with fluorine-18 at 130 to 160° C. in the presence of a phase transition catalyst which is selected from the group consisting of kryptofix 2.2.2. /potassium carbonate (K 2.2.2. /K 2 CO 3 ), tetrabutylammonium hydroxide (TBAOH), tetrabutylammonium bicarbonate (TBAHCO 3 ), cesium hydroxide (CsOH), and a combination thereof, wherein the diaryliodonium salt precursor is represented by the following Chemical Formula 1: wherein Ar− is selected from the group consisting of the following aryl (Ar−) radicals: and X − is selected from among trifluoromethane sulfonate), perfluoro C 2 -C 10 alkyl sulphonate, trifluoroacetate, tetraphenylborate), toluene sulfonate), Br − , and Cl − .