Synthesis of Aryl Fluorides from Potassium Aryltrifluoroborates and Selectfluor® Mediated by Iron(III) Chloride

Abstract

The synthesis of fluorinated arenes by the iron-mediated fluorination of potassium aryltrifluoroborates with Selectfluor ® and potassium fluoride is described. The fluorination reaction uses commercially available reagents and without requiring the addition of exogenous ligands. Fluorinated compounds were obtained in moderate to good yields under mild reaction conditions.

Fluorination of organoboron compounds

“…Dubbaka has reported an FeCl3 / Selectfluor-mediated fluorination of aryl trifluoroborates. 25 However in many cases this procedure led to the formation of ortho-as well as ipsosubstituted regioisomeric products, particularly in the cases of electron-rich aromatic rings. These regioisomers were particularly prevalent with a strong electron-donating group Please do not adjust margins Please do not adjust margins para-or meta-to boron.…”

Modular Construction of Fluoroarenes from a New Difluorinated Building Block by Cross‐Coupling/Electrocyclisation/Dehydrofluorination Reactions

“…While traditional methods like direct fluorination, the Balz–Schiemann reaction, and the Halex reaction have been used extensively, and new functional‐group transformations have been developed, metal‐catalysed transformations are gaining in impact and popularity . Copper‐, iron‐, nickel‐, palladium‐ and silver‐based methods are all known. These novel metal‐based and catalytic methods complement the older (and usually harsher) methods well; all involve assembly of the arene or heteroarene scaffold, complete with the appropriate precursor functionality, before fluorination takes place.…”

Synthesis of 5‐Fluorotriazoles by Silver‐Mediated Fluorination of 5‐Iodotriazoles

“…In the last decades, transition‐metal‐catalyzed/mediated sp 2 C–F bond formation has emerged as a powerful method for the construction of compounds containing aryl fluoride moieties 12. Recently, several groups have reported various sp 2 C–F bond constructions mediated by transition metals including Fe,13 Ni,14 Cu,15 Pd,16 and Ag,17 with electrophilic or nucleophilic fluorinating reagents as the source of fluorine. For example, Hartwig reported a copper‐mediated fluorination of aryl iodides with AgF as fluoride source 15e.…”