Synthesis and Characterization of Stable Iron Pentacarbonyl Radical Cation Salts

Angew Chem Int Ed Engl. 2022 Aug 8;61(32):e202204080. doi: 10.1002/anie.202204080. Epub 2022 Jun 7.

Abstract

The open-shell iron pentacarbonyl cation [Fe(CO)5 ].+ was isolated by deelectronation, i.e., the single-electron oxidation of the parent neutral Fe(CO)5 using [phenazineF ].+ as the [Al(ORF )4 ]- and [F-{Al(ORF )3 }2 ]- salt (RF =C(CF3 )3 ; phenazineF =perfluoro-5,10-bis(perfluorophenyl)-5,10-dihydrophenazine). [Fe(CO)5 ].+ [Al(ORF )4 ]- was fully characterized (scXRD analysis, IR, NMR, EPR, 57 Fe spectroscopy, CV and SQUID magnetization study) and, apart from being a compound of fundamental interest, may serve as a precursor for low-valent iron coordination chemistry.

Keywords: Carbonyl Ligands; Iron; Radical Ions; Weakly Coordinating Anions.