title: New paramagnetic Re(II) compounds with nitrile and cyanide ligands prepared by homolytic scission of dirhenium complexes.
abstract: The preparation and characterization of three new paramagnetic complexes of the 17-electron Re(II) ion are reported. The salts [Re(triphos)(CH(3)CN)(3))][X](2), X = [BF(4)](-) (1), [PF(6)](-) (2), and [Et(4)N][Re(triphos)(CN)(3)] (3) were prepared by homolytic cleavage of the Re-Re bond in [Re(2)(CH(3)CN)(10)][BF(4)](4) or by disruption of the chlorine bridges in [(triphos)Re(mu-Cl)(3)Re(triphos)]Cl (1) (triphos = 1,1,1-tris(diphenylphosphino-methyl)ethane) and characterized by single-crystal X-ray diffraction, infrared and (1)H NMR spectroscopies, cyclic voltammetry, and magnetic susceptibility measurements. Compound 2 undergoes reversible reduction and irreversible oxidation processes while 3 undergoes a reversible reduction, an irreversible oxidation, and a reversible oxidation. The magnetic susceptibility data for 2 and 3 exhibit a strong temperature independent paramagnetic component which is in accord with a highly anisotropic S = (1)/(2) magnetic ground state. The results of this study indicate that dinuclear Re(2)(II,II) starting materials are viable precursors for producing unusual mononuclear Re(II) complexes.
authors.affiliation: Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Schelter
authors.forename: Jitendra K
authors.initials: JK
authors.lastname: Bera
authors.forename: John
authors.initials: J
authors.lastname: Bacsa
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Galán-Mascarós
authors.forename: Kim R
authors.initials: KR
authors.lastname: Dunbar