2.3 Synthesis of Aryl and Hetaryl Fluorides

Abstract Aryl and hetaryl fluorides, as important structural motifs, are widely applied in pharmaceuticals, agrochemicals, positron emission tomography (PET) imaging agents, and organic materials. Profound changes in properties such as solubility, lipophilicity, bioavailability, and/or metabolic stability of the target molecules have been imparted via the introduction of fluorine atoms. Thus, much effort has been contributed to the synthesis of (het)aryl fluorides. In this review, we discuss the key developments in the synthesis of (het)aryl fluorides based on nucleophilic substitution of diazo, (pseudo)halo, nitro, and phenolic hydroxy groups, as well as electrophilic substitution of hydrogen and organometallic groups, both with and without the assistance of transition-metal catalysis.