Direct Trifluoromethoxylation of Aromatics and Heteroaromatics

This chapter is concerned with recent developments of direct trifluoromethoxylation reactions in the synthesis of aryl and heteroaryl trifluoromethyl ethers. The properties of OCF3-bearing arenes and heteroarenes and their applications are discussed. The challenges in the direct synthesis of aryl and heteroaryl trifluoromethyl ethers are described. The timeline of trifluoromethoxylating reagent development is outlined. Anionic and radical approaches utilizing either the trifluoromethoxide anion (–OCF3) or trifluoromethoxy radical (˙OCF3) are then presented, including reaction conditions and substrate scope, and their mechanisms are discussed in detail.