Fluorination Of Arenes Research Articles

Selectfluor-mediated chlorination and fluorination of arenes: late stage functionalization of APIs and its biological effects.

By using APIs previously recovered from expired drugs, it is shown that Selectfluor can act as a reagent for operationally simple late-stage fluorination and chlorination of electron-rich arenes under mild reaction conditions. As shown in mechanistic experiments, aromatic fluorination thereby competes with chlorine-for-fluorine exchange on Selectfluor and subsequent aromatic chlorination, whereat the chloride ions may either be provided by the hydrochloride salt of the respective API or by triethylammonium chloride. Biological testing of the fluorinated or chlorinated APIs at adrenergic, dopaminergic, muscarinergic, opioid or serotoninergic receptors demonstrated that improved binding affinities can be achieved via this straightforward strategy.

A Fruitful Decade of Organofluorine Chemistry: New Reagents and Reactions

A Fruitful Decade of Organofluorine Chemistry: New Reagents and Reactions

A General Copper‐Mediated Nucleophilic 18F Fluorination of Arenes

AbstractMolecules labeled with fluorine‐18 are used as radiotracers for positron emission tomography. An important challenge is the labeling of arenes not amenable to aromatic nucleophilic substitution (SNAr) with [18F]F−. In the ideal case, the 18F fluorination of these substrates would be performed through reaction of [18F]KF with shelf‐stable readily available precursors using a broadly applicable method suitable for automation. Herein, we describe the realization of these requirements with the production of 18F arenes from pinacol‐derived aryl boronic esters (arylBPin) upon treatment with [18F]KF/K222 and [Cu(OTf)2(py)4] (OTf=trifluoromethanesulfonate, py=pyridine). This method tolerates electron‐poor and electron‐rich arenes and various functional groups, and allows access to 6‐[18F]fluoro‐L‐DOPA, 6‐[18F]fluoro‐m‐tyrosine, and the translocator protein (TSPO) PET ligand [18F]DAA1106.