92359-79-0Relevant academic research and scientific papers
Mixed Chloride/Phosphine Complexes of the Dirhenium Core. 2. New Reactions Involving Dimethylphenylphosphine
Albert Cotton,Dikarev, Evgeny V.,Petrukhina, Marina A.
, p. 1949 - 1958 (2008/10/08)
Two geometrical isomers of the composition Re2Cl5(PMe2Ph)3, namely 1,2,7 and 1,3,6, have been prepared. The unusual paramagnetic 1,2,7-Re2Cl5(PMe2Ph)3 (1a), the first analogue of the previously reported trimethylphosphine complex 1,2,7-Re2Cl5(PMe3)3, has been synthesized by carrying out the reaction of octachlorodirhenium anions with PMe2Ph in benzene at room temperature. A different reaction product, 1,3,6-Re2Cl5(PMe2Ph)3 (1b), was obtained when [Bun4N]2Re2Cl8 was reacted with PMe2Ph under the same conditions in acetonitrile. Electrochemical studies revealed that both 1a and 1b, as expected for the Re25+ core, are capable of undergoing a one-electron reduction and a one-electron oxidation to yield the respective Re24+ and Re26+ dinuclear complexes. Both processes have been accomplished chemically for the 1,2,7-isomer in the present work. One-electron reduction of 1a by cobaltocene followed by nonredox substitution of a chloride ligand in the resulting anionic species by PMe2Ph affords triply bonded 1,2,7,8-Re2Cl4(PMe2Ph)4 (2), only the second example of this rare stereochemistry with a cis-configuration of monodentate phosphines at both metal atoms in the large M2X4(PR3)4 class of compounds. One-electron oxidation of 1a in the presence of a chloride source, Bun4NCl, resulted in a quadruply bonded Re2Cl6(PMe2Ph)2 (3), completing the full series of Re2Cl8-x(PMe2Ph)x (x = 2, 3, 4) compounds with Re2n+ (n = 6, 5, 4) cores. The crystal structures of all complexes 1-3 have been investigated by X-ray diffraction. The crystallographic parameters for these structures are as follows: 1,2,7-Re2Cl5(PMe2Ph)3 (1a), triclinic space group P1 with a = 9.350(3) A, b = 11.102(1) A, c = 14.558(3) A, α = 101.34(2)°, β = 92.81(2)°, γ = 90.80(2)°, and Z = 2; 1,3,6-Re2Cl5(PMe2Ph)3 (1b), monoclinic space group P21/c with a = 11.202(4) A, b = 14.357(6) A, c = 19.509(5) A, β = 97.84(3)°, and Z = 4; 1,2,7,8-Re2Cl4(PMe2Ph)4 (2), triclinic space group P1 with a = 11.847(4) A, b = 12.094(3) A, c = 13.056(5) A, α = 76.111(8)°, β = 88.523(9)°, γ = 88.95(2)°, and Z = 2; 1,7-Re2Cl6(PMe2Ph)2, (3), triclinic space group P1 with a = 9.209(1) A, b = 11.480(2) A, c = 13.389(2) A, α = 81.74(2)°, β = 69.89(2)°, γ = 66.35(2)°, and Z = 2. The Re-Re bond lengths in the Re24+ (2), Re25+ (1a and 1b), and Re26+ (3) centered molecules (2.260(1), 2.2313(4), 2.219(1), and 2.214(1) A) are consistent with bond orders of 3.0, 3.5, and 4.0, respectively.
Cobaltocene reductions of multiply bonded dirhenium complexes: Isolation, characterization, and reactivity studies of [(η5-C5H5)2Co][Re 2(O2CR)4Cl2], [(η5-C
Dunbar, Kim R.,Walton
, p. 5 - 10 (2008/10/08)
Full title: Cobaltocene reductions of multiply bonded dirhenium complexes: Isolation, characterization, and reactivity studies of [(η5-C5H5)2Co][Re 2(O2CR)4Cl2], [(ηs
