89530-60-9Relevant academic research and scientific papers
Dirhenium(II) complexes containing monodentate and polydentate nitrile ligands
Chantler, James,Fanwick, Phillip E.,Walton, Richard A.
, p. 215 - 220 (2000)
The complex Re2Cl4(μ-dppa)2 (dppa = Ph2PNHPPh2) has been reacted with EtCN and PhCN to afford the complexes [Re2Cl3(μ-dppa)2(NCR)2]PF6 (R = Et or Ph), [Re2Cl3(μ-HN2C2Et2)(μ-dppa)2(NCEt)]Cl and [Re2Cl3(μ-HN2C2Et2)(μ-dppa)2(NCEt)](PF6)2 which are derivatives of the [Re2]4+, [Re2]5+ and [Re2]6+ cores, respectively. This behaviour is similar to the reactions of Re2Cl4(μ-dppm)2 (dppm = Ph2PCH2PPh2) with monodentate nitriles. The reactions of Re2Cl4(μ-dppm)2 with the polydentate nitrile ligands 1,4-dicyanobenzene (1,4-DCB), 1,4-dicyanobut-2-ene (1,4-DCBE) and tris(2-cyanoethyl)phosphine (CEP) also give complexes of this same type in which the nitrile ligand utilizes only one of its CN groups. This is confirmed by an X-ray crystal structure determination of [Re2Cl3(μ-dppm)2(1,4-DCB)2]PF6, in which the Re≡Re bond is retained (Re-Re distance 2.2637(12) A?) and the 1,4-DCB ligands are monodentate. (C) 2000 Elsevier Science S.A.
Dirhenium complexes containing pairs of bridging acetate and bis(diphenylphosphino)amine ligands. Cis and trans isomers of the type [Re2(O2CCH3)2X2(Ph 2PNHPPh2)2]n+ (X = Cl, Br; n = 0, 1)
Derringer, Daniel R.,Fanwick, Phillip E.,Moran, Justin,Walton, Richard A.
, p. 1384 - 1389 (2008/10/08)
The reactions of dirhenium(III) carboxylates of the type Re2(O2CCH3)2X4(H 2O)2 (1, X = Cl, Br) with bis(diphenylphosphino)amine (dppa) in hot ethanol afford reduced, mixed-halide-phosphine complexes with two, one, or zero bridging acetate ligands. Yellow Re2(O2CCH3)X4(dppa)2 (2) is produced in reactions of very short duration (ca. 3 min), while longer reaction times (ca. 15 min) favor yellow trans-[Re2(O2CCH3)2X 2(dppa)2]X (3). After several days, under these same reaction conditions, cis-Re2(O2CCH3)2X 2(dppa)2 (4) is produced. While 2 can undergo reductive decarboxylation to give Re2X4(dppa)2 (5), the latter species does not appear to be an important precursor to 4, as it is in an analogous system involving reactions of 1 with bis(diphenylphosphino)methane (dppm) (see: J. Am. Chem. Soc. 1988, 110, 5024). The most important reaction pathway to 4 is via the sequence 1 → 2 → 3 → 4. The complex 4 (X = Cl) reacts with the one-electron oxidant [(η5-C5H5)2Fe]PF6 to produce paramagnetic cis-[Re2(O2CCH3)2Cl 2(dppa)2]PF6 (6). The redox properties of 2-6 have been studied by the cyclic voltammetric technique. The pair of complexes 4 and 6 (X = Cl) were characterized structurally by X-ray crystallography. Crystal data for 4 at 19°C: monoclinic space group P21/c, a = 14.267 (2) A?, b = 15.831 (4) A?, c = 23.824 (3) A?, β = 100.163 (9)°, V = 5296 (3) A?3, Z = 4. The structure was refined to R = 0.034 and Rw = 0.049 for 5026 data with F2 > 3.0σ(F2). Crystal data for 6 at -100°C: monoclinic space group C2/c, a = 34.539 (5) A?, b = 14.015 (4) A?, c = 26.018 (5) A?, β = 103.83 (2)°, V = 12 229 (9) A?3, Z = 8. This structure was refined to R = 0.047 and Rw = 0.065 for 6311 data with F2 > 3.0σ(F2).
