Electronic Interactions between Ferrocenyl Units Facilitated by the Cobalt Bis(dicarbollide) Anion Linker: An Experimental and DFT Study

摘要

> The electronic interaction between two terminal ferrocenyl units connected by the cobalt bis(dicarbollide) anion linker was investigated. The bis(ferrocenylethynyl)cobalt bis(dicarbollide) anion ( 3 ) linking the two ferrocenyl units with the cobalt bis(dicarbollide) anion was synthesized by the reaction of a zinc derivative of ethynylferrocene with the diiodocobalt bis(dicarbollide) anion using Pd 0 catalyst in 75?% yield. Complex 3 was unambiguously characterized by NMR and IR spectroscopy, mass spectrometry, and single‐crystal X‐ray crystallography. The X‐ray structure of 3 reveals that the two ferrocenyl units are perpendicular to each other with a total distance of 1.86 nm between the two Fe metal centers. The cyclic voltammogram of 3 shows a single oxidation potential corresponding to the two ferrocenyl units. Time‐dependent density functional theory (TD‐DFT) studies on complex 3 in tandem with UV/Vis spectroscopic analysis indicate the dominance of the dicarbollide moiety in the LUMOs, and HOMO→LUMO transitions at 435 nm illustrate the charge transfer from the two ferrocenyl units to the cobalt bis(dicarbollide) linker.