The Wieland reaction, which involves the attack of a triphenyltnethyl radical on aromatic substrates in the preseuce of benzoyl'peroxide, has been studied in detail. Isomer distributions and relative reactivities have been determined for substrates of anisole, chlorobenzene, methyl benzoate and benzotrifluoride. The order of reactivity observed (C6H50CI13> CsH5Cl> C6H5H> CeH5C02CH3> C&CF3> C6H6N02) indicates the ...