Pyridine•BrF3, the Missing Link for Clean Fluorinations of Aromatic Derivatives

This work demonstrates the unique features of the never used before Py center dot BrF3 complex in the field of aromatic organic fluorinations. The main disadvantage of the noncomplexed BrF3 is the fact that usually, in addition to the desired fluorination, a parallel electrophilic aromatic bromination takes place as well. Use of the Py center dot BrF3 complex reduces this electrophilic bromination, which is observed with most reagents based on fluorine and bromine [BrF].