Visible-light photolytic synthesis of multinuclear and dendritic iron-nitrile cationic complexes

Article abstract of DOI:10.1021/ic800100k

Multinuclear and dendritic iron-nitrile piano-stool cationic complexes were synthesized in quantitative yield by a single-step synthesis involving visible-light photolysis of the complex [CpFe(η⁶-toluene)] [PF₆]. This synthetic strategy was applied to mono-, bis- and tris-nitrile ligands and to new nitrile-terminated dendrimers containing 9, 27, and 81 tethers. All the synthesized products are deep red solids or red waxy products, highly stable to air and moisture. They were characterized by ¹H, ¹³C, and ³¹P NMR, elemental analysis, UV-vis spectroscopy, and cyclic voltammetry (single reversible oxidation wave to Fe^III). Only the para-disubstituted arene dinitrile diiron complex shows two separated reversible waves indicating some electronic communication between the iron centers through the nitrile ligands.