Electronic Structures, Spectroscopy, and Electrochemistry of [M(diimine)(CN-BR<sub>3</sub>)<sub>4</sub>]<sup>2–</sup> (M = Fe, Ru; R = Ph, C<sub>6</sub>F<sub>5</sub>) Complexes
Danh X. Ngo, Sarah A. Del Ciello, Alexandra T. Barth, Ryan G. Hadt, Robert H. Grubbs, Harry B. Gray, Brendon J. McNicholas
Abstract
Complexes with the formula [M(diimine)(CN-BR3)4]2–, where diimine = bipyridine (bpy), phenanthroline (phen), 3,5-trifluoromethylbipyridine (flpy), R = Ph, C6F5, and M = FeII, RuII, were synthesized and characterized by X-ray crystal structure analysis, UV–visible spectroscopy, IR spectroscopy, and voltammetry. Three highly soluble complexes, [FeII(bpy)(CN-B(C6F5)3)4]2–, [RuII(bpy)(CN-B(C6F5)3)4]2–, and [RuII(flpy)(CN-B(C6F5)3)4]2–, exhibit electrochemically reversible redox reactions, with large potential differences between the bpy0/– or flpy0/– and MIII/II couples of 3.27, 3.52, and 3.19 V, respectively. CASSCF+NEVPT2 calculations accurately reproduce the effects of borane coordination on the electronic structures and spectra of cyanometallates.