85993-34-6Relevant academic research and scientific papers
Reactions of the dirhenium(in, iii) complex c/Y-Re2(n-O2CMe)2C14(H2O)2 that lead to the dirhenium(ni, ii) complexes Re2(u-O2CMe)Cl4(PR3)2 and tetrarheniumcyclodiyne clusters of the type Re4(u-O)4Cl4(PR3)4
Bera, Jitendra K.,Lau, Sophia S.,Famvick, Phillip E.,Walton, Richard A.
, p. 4277 - 4284 (2007/10/03)
The reaction of cw-Re2(u-O2CMe)2Cl4(H2O)21 with P(C6H4OMe-/>)3 gives the tetranuclear complex Re4(u-O)4Cl4[P(C6H4OMe-p)3]414 along with the salt [(C6H4OMe-p)3PMe]2Re2Cl815. Compound 14 is the first symmetrical, neutral, tetrarheniumcyclodiyne type cluster that contains phosphine ligands. Complexes of this same type with PPh3 (16) and PMe2Ph (17) have been prepared by alternative methods but have poor solubility properties. The paramagnetic complex Re2(u-O2CMe)Cl4(PPh3)2 2, which is prepared from 1 by reaction with PPh3, undergoes phosphine substitution reactions when treated with dichloromethane solutions of other phosphines. Simple non-redox reactions can occur upon reaction of 2 with monodentate and bridging bidentate phosphines to afford complexes of the types Re2(u-O2CMe)Cl4(PR3)2 [PR3 = PBz3 3, P(C6H4OMe-/j)3 4 or PMePh2 5] and fra/w-Re2(u-O2CMe)Cl4(u-PP)2 [PP = dppm 9, Ph2PNHPPh210 or (Ph2P)2C=CH211J. However, reactions that lead either to reduction to dirhenium(ii) complexes or Re-Re bond cleavage are encountered in the case of the reactions of 2 with PMePh2, PMe2Ph, PCy3 and dppe; these have led to the isolation of Re2Cl4(PMePh2)4 6, Re2Cl4(PMe2Ph)4 7, ;wi?/_/ra/u-ReOCl3(PCy3)2 8, a-Re2Cl4(dppe)212, and /ra/i.y-[ReO2(dppe)2]Cl 13. The structures of compounds 3, 8, 13, 14 and 15 have been determined by X-ray crystallography. ; The Royal Society of Chemistry 2000.
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.
Reactivity of the dirhenium(III) carboxylate complexes Re2(O2CCH3)2X4(H 2O)2 (X = Cl or Br) toward monodentate phosphines. A novel disproportionation reaction leading to dirhenium(IV,II) alkoxide complexes of the type (RO)2X2ReReX2(PPh3)2 (X = ...
Chakravarty, Akhil R.,Cotton, F. Albert,Cutler, Ann R.,Walton, Richard A.
, p. 3619 - 3624 (2008/10/08)
Full title: Reactivity of the dirhenium(III) carboxylate complexes Re2(O2CCH3)2X4(H 2O)2 (X = Cl or Br) toward monodentate phosphines. A novel disproportionation reaction leading to dirhenium(IV,II) alkoxide complexes of the type (RO)2X2ReReX2(PPh3)2 (X = Cl or Br; R = Me, Et, or Pr). The reactions of quadruply bonded dirhenium(III) carboxylate complexes of the type Re2(O2CR)2X4L2 (X = Cl or Br; R = CH3 or C2H5; L = H2O, py, DMF, or Me2SO) with monodentate tertiary phosphines in alcohol solvents have been examined. Whereas Re2(O2CCH3)2Cl4L 2 (L = H2O or py) reacts with PMe3, PMe2Ph, and PMePh2 in ethanol to give the dirhenium(II) complexes Re2Cl4(PR3)4, the reactions between Re2(O2CR)2X4L2 (X = Cl or Br; R = CH3 or C2H5; L = H2O, DMF, or Me2SO) and PPh3 in refluxing alcohol solvents ROH (R = Me, Et, n-Pr, or i-Pr) afford red crystalline, diamagnetic complexes of stoichiometry Re2(OR)2X4(PPh3)2. The ethoxide derivative has been characterized by X-ray crystallography and shown to possess the novel structure (EtO)2Cl2ReReCl2(PPh3)2. This is best described formally as a Re(IV)-Re(II) complex that has been derived from the Re(III)-Re(III) core by an intramolecular disproportionation. A comparison is made between the properties of these new mixed halide-alkoxide complexes and those of their symmetrical Re(III)-Re(III) halide analogues Re2X6(PR3)2. Crystal and structural data for Re2Cl4(OEt)2(PPh3)2: space group P21/c with a = 10.782 (3) ?, b = 14.330 (3) ?, c = 26.924 (7) ?, β = 96.98 (2)°, V = 4129 (3) ?3, Z = 4. The Re-Re distance is 2.231 (1) ?.
