[(hydrido)(1,2-bis(di-tert-butylphosphino)ethane)(2,6-dimethylphenyl isocyanide)platinum](PF6) | 154293-14-8

• 英文名称: [(hydrido)(1,2-bis(di-tert-butylphosphino)ethane)(2,6-dimethylphenyl isocyanide)platinum](PF6)
• CAS: 154293-14-8
• 化学式: C₂₇H₅₀NP₂Pt*F₆P
• 分子量: 790.692
• InChiKey: QMAFZYIVUNLOPR-UHFFFAOYSA-N

反应信息

• 作为产物：
  描述：

  [(1,2-bis(di-tert-butylphosphino)ethane)(2,6-dimethylphenyl isocyanide)platinum(II)](PF6)2 在 NaClO₄ 作用下， 以 乙腈 为溶剂， 以13%的产率得到[((1,2-bis(di-tert-butylphosphino)ethane)(2,6-dimethylphenyl isocyanide)platinum)2platinum](PF6)2
  参考文献：
  名称：

  含螯合二膦的异氰酸铂簇的电化学制备。前所未有的三核铂络合物，其中包括配位不饱和金属中心，[{Pt（diphosphine）（isocyanide）} 2Pt]（PF6）2

  摘要：

  A controlled-potential electrolysis was performed on mononuclear platinum(II) complexes containing aromatic isocyanide (RNC) and diphosphine (diphos) ligands, [Pt(diphos)((RNC)2](PF6)2 diphos = cis-1,2-bis(diphenylphosphino)ethene (dppen) (1), 1,2-bis(diphenylphosphino)ethane (dppe) (2),1,3-bis(diphenylphosphino)propane (dppp) (3),1,4-bis(diphenylphosphino)butane (dppb) (4), and 1,2-bis(di-tert-butylphosphino)ethane (dtbpe) (5); R = 2,6-dimethylphenyl or 2,4,6-trimethylphenyl), which were derived from the reaction of PtCl2(COD) with diphos, RNC, and NH4PF6. Electrolyses of complexes 1-4 at a mercury-pool electrode consumed 1 F mol-1 in acetonitrile at -1.45 to -1.5 V (vs Cp2Fe/CP2Fe+), which gave dinuclear platinum(I) complexes, [Pt4(diphos)2(RNC)2] (PF6)2 (diphos = dppen (6), dppe (7), dppp (8), and dppb (9)). The compounds were characterized by IR, electronic, and H-1 and P-31{H-1} NMR spectroscopy and X-ray crystallographic and EXAFS (extended X-ray absorption fine structure) analyses. Complex 8b (R = 2,4,6-Me3C6H2, diphos = dppp) crystallizes in the monoclinic system, space group P2(1)/c, with a = 14.941(4) angstrom, b = 19.268(6) angstrom, c = 26.002(9) angstrom, beta = 101.23(2)degrees, and Z = 4 (R = 0.059 and R(w) = 0.051 for 5704 independent reflections with I > 3sigma(I)). Complex 8b consists of two platinum atoms, each coordinated by one isocyanide, one diphosphine as a chelating ligand, and the neighboring platinum atom in a square planar array. The length of the Pt-Pt bond is 2.653(1) angstrom. EXAFS analyses showed that the Pt-Pt bond lengths of 6-9 fall within the narrow range of 2.625-2.653 angstrom. Electrolyses of 1, 3, and 5 consumed 1.5 F mol-1 at ca. -1.8 V, which gave trinuclear platinum complexes, [{Pt(diphos)(RNC)}2Pt](PF6)2 (diphos = dppen (13), dppp (14), and dtbpe (15)). Complex 13a (R = 2,6-Me2C6H3) crystallizes in the monoclinic system, space group P2/n, with a = 14.956(4) angstrom, b = 12.395(2) angstrom, c = 22.923(7) angstrom, beta = 104.35(2)degrees, and Z = 2 (R = 0.048 and R(w) = 0.046 for 2872 independent reflections with I > 3sigma(I)); complex 14a (R = 2,6-Me2C6H3) crystallizes in the monoclinic system, space group P2(1), with a = 15.491(3) angstrom, b = 22.575(5) angstrom, c = 10.883(3) angstrom, beta = 107.48(2)degrees, and Z = 2 (R = 0.056 and R(w) = 0.038 for 3156 independent reflections with I > 3sigma(I)); and complex 15a (R = 2,6-Me2C6H3) crystallizes in the monoclinic system, space group C2/c, with a = 19.489(6) angstrom, b = 15.284(5) angstrom, c = 25.804(6) angstrom, beta = 116.34(2)degrees, and Z = 4 (R = 0.045 and R(w) = 0.033 for 2904 independent reflections with I > 3sigma(II). The three platinum atoms were arranged in a linear array with Pt-Pt bond distances of 2.615(1) angstrom (13a), average 2.640 angstrom (14a), and 2.6409(8) angstrom (15a). The outer Pt atoms are coordinated by one isocyanide and one chelating diphosphine, and the central Pt atom is bound only to the two neighboring Pt atoms, resulting in a coordinatively unsaturated platinum center. The coordinatively unsaturated triplatinum complexes 13-15 have 40 valence electrons and are extremely electron-deficient. In the electrolysis of 5a, further reduction led to the formation of a mononuclear hydride complex of platinum, [PtH(dtbpe)-(2,6-Me2C6H3NC)]PF6 (16a). The potentiostatic electrolysis of 2 consumed 1.5 F mol-1 to afford the coordinatively saturated triplatinum complex, [{Pt(dppe)(RNC)}2Pt(RNC)2](PF6)2 (10), instead of the unsaturated trimer. The analogous compounds [{Pt(diphos)(RNC)}2Pt(RNC)2](PF6)2 (diphos = dppen (11) and dtbpe (12)) were also obtained from the reaction of [Pt3-(RNC)8]2+ with diphosphines. Complex 11a (R = 2,6-Me2C6H3) crystallizes in the monoclinic system, space group P2(1)/c, with a = 13.403(3) angstrom, b = 16.126(4) angstrom, c = 21.944(8) angstrom, beta = 98.57(2)degrees, and Z = 2 (R = 0.054 and R(w) = 0.040 for 3064 independent reflections with I > 3 sigma(I)). The Pt-Pt bond length of 2.655(1) angstrom is longer by 0.040 angstrom than that of 13a. A two-electron reduction of 4 at ca. -1.8 V yielded a Hg-Pt mixed-metal cluster, [HgPt6(dppb)2(RNC)8] (17). The length of methylene chain in the diphosphine ligands dramatically influences the structure of the metal-metal bonded platinum clusters. Extended Huckel MO calculations were carried out on the models, [{Pt(PH3)2(HNC)}2Pt]2+ and [{Pt(PH3)2(HNC)}2Pt(HNC)2]2+, for the coordinatively unsaturated and saturated trimers.

  DOI：

  10.1021/om00016a045