Sobre uma degenerescência acidental nos deslocamentos químicos de RMN de 31P{¹H} em complexos difosfínicos de rutênio On an accidental degeneracy in the 31P{¹H} NMR chemical shifts in ruthenium diphosphine complexes
The [RuCl(bipy)(dppb)(4-pic)]PF6 complex was prepared and fully characterized. The X-ray crystal structure of this complex was determined in order to make an unambiguous distinction between the two possible positions of the 4-methylpyridine ligand (4-pic) in the compound: trans to phosphorus atom or trans to nitrogen atom. The [RuCl(bipy)(dppb)(4-pic)]PF6 complex exhibits an unusual temperature-dependent accidental degeneracy of the 31P chemical shifts in its solution NMR spectrum.