Electrophilic amination of 4-fluorophenol with diazenes: a complete removal of the fluorine atom

J Org Chem. 2004 Mar 19;69(6):2224-7. doi: 10.1021/jo035856b.

Abstract

The electrophilic amination of 2-fluorophenol, 4-fluorophenol, and 2-chlorophenol was observed to occur as a result of their treatment with diazenes 1-4 under mild reaction conditions in the presence of ZrCl(4). The products originating from the 2-fluorophenol or 2-chlorophenol can be considered as "normal" products of amination. On the other hand, the 2-chloro-4-amino-substituted phenols obtained from the 4-fluorophenol seem to be formed in a process that involves an ipso amination, the complete removal of the fluorine atom, and the introduction of the chlorine atom.