Synthesis of 3-chloro-6-((4-(di-tert-butyl[18F]-fluorosilyl)-benzyl)oxy)-1,2,4,5-tetrazine ([18F]SiFA-OTz) for rapid tetrazine-based 18F-radiolabeling

An efficient method to prepare the F-18-labeled tetrazine-derivative [F-18]-SiFA-OTz for bioorthogonal radiochemistry was developed. [F-18]-SiFA-OTz can be synthesized with a radiochemical yield of 78 +/- 5% within 25 min and can quantitatively react with a model strained dienophile, trans-cyclooctenol.