Asymmetric Diaryliodonium Tosylates Useful for Metal-free Arylations

Asymmetric diaryliodonium salts bearing 1,3,5-trimethoxyphenyl (TMP) and an aryl group, are applicable to multiple arylation reactions without using a transition metal complex.¹⁾ For example, the 4-biphenylyl derivative (1) can smoothly react with phenol, sodium benzenesulfinate, and sodium azide as O-, N- and S- nucleophiles to give the corresponding O-, N- and S-aryl products.²⁾ Furthermore, reactions with ¹⁸fluorinating agents have been reported. This ¹⁸F labeling procedure can be applied to the synthesis of molecular probe contrast agents for PET (Positron Emission Tomography) scan diagnostics.³⁾