Ullmann Diaryl Ether Synthesis

Abstract

The copper reagent‐promoted coupling between alkali phenoxides and aryl halides to form diaryl ethers is generally referred to as the Ullmann diaryl ether synthesis. This reaction is usually carried out at high temperatures either in the absence of solvent or in an inert solvent. The study finds that reaction between phenols with electron‐donating groups and aryl halides with electronwithdrawing substituents works readily. In addition, this reaction has some drawbacks. This reaction has been applied for the preparation of diaryl ethers.