A mild procedure for the selective formation of aryl ethers and triaryl diethers using arene–M–CP cations (M = Fe, Ru; Cp =η5-cyclopentadienyl)

Reaction of (η6-1,3-dichlorobenzene)(η5-cyclopentadienyl)iron hexafluorophosphate with aryl oxides from protected tyrosines proceeds under mild conditions to generate aryl ethers, and the halogens may be displaced sequentially, allowing the preparation of unsymmetrical or symmetrical triaryl diethers; (η6-N-acetyl-4-chlorophenylalanine methyl ester)(η5-cyclopentadienyl)ruthenium hexafluorophosphate was prepared and was shown to react with protected tyrosine aryl oxide to generate dityrosine derivatives, and a mild photochemical method for demetallation of the arene–M–Cp (Cp =η5-cyclopentadienyl) complexes is described.