The Syntheses and Crystal Structures of cis-[Bis(diphenylphosphino)methane][1,2-bis(diphenylphosphlno)ethane] dicarbonylmolybdenum(O) and cis-[1,2-Bis(diphenylphosphino)ethane] [cis-1,2-bis(diphenylphosphino) ethylene]dicarbonylmolybdenum(0)

The title compounds, Mo(CO)₂(Ph₂PCH₂PPh₂)(Ph₂PCH₂CH₂PPh₂), Mo(CO)₂(dppm)(dppe) 1, and Mo(CO)₂(Ph₂PCH₂CH₂PPh₂)(Ph₂PCH = CHPPh₂), Mo(CO)₂(dppe)(cis-vpp) 2, were prepared from Mo(CO)₆ and the corresponding bidentate diphosphine ligands in n-decane under nitrogen atomosphere. Crystals of 1 are monoclinic, space group P 2₁/c, with a = 19.072(3), b = 11.348(3), c = 23.57(1) Å, β = 99.64(3)°, Z = 4, and the final residual R(F) = 0.044 for 4810 observed reflections; data of 2 are triclinic, space group P 1, with a = 12.091(3), b = 12.186(8), c = 18.934(5) Å, α = 96.93(4),β = 108.15(2), γ = 107.08(4)deg;, Z = 2, and the final residual R(F) = 0.058 for 4570 observed reflections. The distortion of compound 1 is more pronounced than that of compound 2, The two Mo-P lengths in the same bidentate chelate ligand for both compounds are different. Among them, the two larger Mo-P bond lengths for compound 2 are similar, but significantly different for 1.     

Unique conformation and packing structure of p-sulfonatocalix[5]arene induced by 1,2-bis(pyridinium)ethane compounds

In the presence of 1,2-bis(4,4'-dipyridinium)ethane, p-sulfonatocalix[5]arene (C5AS) adopts an unseen partial-cone conformation to form back-to-back dimers, whereas C5AS crystallizes in face-to-face dimers to form a wavy layer, rather than the expected bilayer, arrangement upon complexation with 1,2-bis(pyridinium)ethane.     

The reaction of para-tolydiazonium tetrafluoroborate with bis (dinitrogen)-bis(1,2-bis(diphenylphosphino)ethane)molybdenum

Reactions of para-tolyldiazonium tetrafluoroborate with trans-Mo(N₂)₂ (dppe)₂ (where dppe = 1,2-bis(diphenylphosphino ethane) result in the oxidation of the molybdenum complex with complete loss of dinitrogen. A similar reaction occurs with MoBr(N₂)(dppe)₂.     

Synthesis and Crystal Structure of cis - 1,2- Dicy ano- 1,2- b is（ 2- me thyl- 4-bromo-3-thienyl）ethane

The title compound cis-1,2-dicyano-1,2-bis（2-methyl-4-bromo-3-thienyl）ethane has been synthesized and structurally characterized by X-ray single-crystal diffraction method. Crystal data： triclinic, space group P1^1, Z = 2, C14H8Br2N2S2, Mr = 428.16, a = 6.9410（5）, b = 11.0150（9）, c = 11.1760（8） A, α = 70.3390（10）,β = 76.1860（10）, γ = 79.5490（10）°, V= 776.59（10） A^3, Dc = 1.831 g/cm^3, μ（MoKα） = 5.478 mm^-1, F（000） = 416, R = 0.0487 and wR = 0.1453 for 2456 observed reflections with I 〉 2σ（/）. X-ray analysis reveals that the two thiophene rings are significantly twisted with an average dihedral angle of 57.45°. The molecule adopts a photo-active antiparaUel conformation and the distance between the two reactive C atoms of thiophene rings is 3.465（8）A. These structural elements which exhibit a suitable geometry are extensively explored for photochromic behavior in the crystalline state.     

Vibrational Spectroscopic Study of [1,2-bis(4-pyridyl)ethane]metal(II) Tetracyanonickelate(II). 2 m-Xylene Clathrates

Four new Hofmann-type clathrates of the form M(bpa)₂Ni(CN)_4· 2m-xylene (M = Mn , Fe , Co and Ni; bpa = 1,2-bis(4-pyridyl)ethane) have been synthesized and characterized by vibrational spectroscopy. The M(bpa)₂Ni(CN)₄ (M = Fe and Co) host structure is similar to the classical Hofmann-type host framework composed of layers of a two dimensional catena-metal tetra--cyanonickelate(II) network, but in M(bpa)₂Ni(CN)₄ (M = Mn and Ni), the Ni(CN)₄ moiety behaves as a bidentate –[NC-Ni(CN)₂-CN–]– unit in the host framework.