Synthesis of o-brominated diaryl ethers using symmetrical iodonium salts: Application to the synthesis of Bastadin precursors

Abstract

The coupling of o-brominated phenols with symmetrical iodonium salts for the construction of the corresponding diaryl ethers was studied. Bis-(2-benzyloxy-5-formyl-phenyl)-iodonium bromide 6b, only once mentioned in the literature, was fully characterized and tested for the synthesis of Bastadin related diaryl ethers.

Chemistry of Polyvalent Iodine

“…735 The O-arylation of the appropriate phenols using symmetrical iodonium salts has been utilized in the synthesis of hydroxylated and methoxylated polybrominated diphenyl ethers, some of which are related to natural products. 737,738 In particular, several polybrominated diphenyl ethers 373 were prepared by the reaction of iodonium salt 371 with phenols 372 in N,N-dimethylacetamide solution under basic conditions (Scheme 122). 737 Arylations with aryliodonium salts can be effectively catalyzed by transition metals.…”

Room Temperature, Metal-Free Synthesis of Diaryl Ethers with Use of Diaryliodonium Salts

“…The synthesis of diaryl ethers from phenols and diaryliodonium salts was reported already in the 1950s . The reaction employed diaryliodonium halides and inorganic bases in protic solvents, and required prolonged reaction times and high temperature to give diaryl ethers in moderate to good yields. − …”