cis-Bis(2,2′-bipyridine)bis(pyridine)ruthenium(II) salts: a spectroscopic and structural study

Abstract

Claims that cis-bis(2,2′-bipyridine)bis(pyridine)ruthenium(II) salts, cis-[Ru(bipy)₂(py)₂]X₂, form covalent hydrates when treated with hydroxide ion are shown to be in error. Previously reported n.m.r. data are shown to have been incorrectly interpreted, and a full analysis of the two-dimensional ¹H n.m.r. spectra of the complex cation is presented. The crystal structure of the double salt cis-[Ru(bipy)₂(py)₂][BF₄]₂·0.5[Hpy][BF₄][space group P, a= 1.018 8(2), b= 1.219 7(2), c= 1.559 2(2) nm, α= 70.82(2), β= 73.74(2), γ= 72.14(2)°, and Z= 2; R= 0.12 for 1 380 independent reflections with |F²| > σ(F²)] reveals all the N-heterocyclic rings to be conventionally aromatic.