Syntheses, structures, and properties of novel molybdenum and tungsten complexes of fullerenes

The synthesis and characterization of several fullerene-based organometallic complexes containing Mo and W is reported.     

Synthesis and crystal structure of a molybdenum complex of fullerene, [Mo(η 2–C60)(CO)2(dpphen)(dbf)·0.63CS2] (dpphen = 4,7-diphenyl-1,10-phenanthroline; dbf = dibutyl fumarate)

The molybdenum complex [Mo( ²-C₆₀)(CO)₂(dpphen)(dbf)] (1) [dpphen = 4,7-diphenyl-1,10-phenanthroline; dbf = dibutyl fumarate] has been prepared and structurally characterized by X-ray diffraction analysis. In the molecule of (1), the coordination geometry of the Mo atom is distorted octahedral with the phen (1,10-phenanthroline) group of dpphen and two CO groups in the equatorial plane. The Mo atom binds in an ²-fashion to the C—C bonds of C₆₀and dbf. The two C—C bonds are almost mutually orthogonal.     

四核铜原子簇化合物Cu4(c-C6H11CSS2)4的合成和结构研究

环己基甲荒酸六氢吡啶盐与氯化铜反应,产物经二硫化碳重结晶,得四核铜原子簇化合物Cu_4(c-C_6H_(11)CSS_2)_4,用X射线单晶衍射法测定了它的晶体结构,其空间群为C_(4h)~4-P4_2/n晶胞参数a=b=15.125(5)(?),c=8.514(2)(?),α=β=γ=90°,V=1948(1)(?)~3,Z=2,929个衍射点参与修正,R=0.040.分子中Cu_4呈变形四面体构型。产物形成时,c-C_6H_(11)CSS~-与Cu~(2+)有氧化-还原反应发生。文章对产物形成的机理作了探讨。     

Syntheses and X-ray crystal structures of dumbbell-shaped bis-fullerene tungsten and molybdenum complexes

In the first neutral bis-fullerene complexes with tungsten(0) and molybdenum(0) [M(eta 2-C60)2(CO)2(dbcbipy)] [M = W and Mo, dbcbipy = 4,4'-di(butyl carboxyl)-2,2'-bipyridine] synthesized in solution, the metal atom coordination is distorted octahedral with two CO groups and the bipy group of dbcbipy in the equatorial plane and the metal atom binding in an eta 2-fashion to C-C bonds of two C60 at axial orientation to give a dumbbell shaped molecule.     

Synthesis and crystal structure of a novel decanuclear silver cluster complex [Ag(SC6H2Pri(3)-2,4,6)](10).2CHCI3.C2H5OH

The cluster [Ag(SC6H2Pri(3)-2,4,6)]10 (1) contains a 20-membered ring of alternating silver and sulfur atoms, which is compactly folded; the sulfur atoms are doubly bridging and each silver atom exhibits linear two-coordination in the primary Ag-S interactions.     

Synthesis and crystal structure of a novel pentaconta-nuclear silver anionic cluster complex [HNEt3]4[Ag50S7(SC6H4But-4)40].2CS(2).6C3H6O

A silver 4-tert-butylthiophenolate complex generated in situ reacted with CS2 in acetone to give an anionic cluster [Ag50S7(SC6H4But-4)40]4-, the core of which consists of fifty silver atoms and forty-seven sulfur atoms, shaped like a discus with a diameter of ca. 2.0 nm.     

Synthesis and Structures of Bis(alkene) Complexes of Tungsten and Molybdenum, [M(CO)2(dpphen)(dbf)2] (M = W or Mo; dpphen = 4,7‐diphenyl‐1,10‐phenanthroline; dbf = dibutylfumarate)

Tungsten and molybdenum complexes [M(CO)₂(dpphen)(dbf)₂] (M = W 1 or Mo 2 ; dpphen = 4,7‐diphenyl‐1,10‐phenanthroline; dbf = dibutylfumarate) have been synthesized and structurally characterized by X‐ray diffraction analysis. In both complexes which have similar structure, the metal atom co‐ordination is distorted octahedral with dpphen and two CO groups in the equatorial plane and the metal atom binds in an η²‐fashion to the C–C bonds of two dbf ligands. The two C–C bonds are almost mutually orthogonal. The two complexes are different in conformation which result from face selection of the two dbf ligands for coordination to the metal atom.     

人工合成胰岛素的精神代代相传——纪念我国人工合成结晶牛胰岛素50周年

我国科学家从1958年开始,经过6年多的曲折努力,终于在1965年9月成功地获得了人工全合成牛胰岛素的晶体。这是世界上第一个人工合成的具有生物活力的结晶蛋白质,它标志着人类在认识生命、探索生命奥秘的征途中迈出了关键性的一步,从而成为我国自然科学发展史上的一个重要里程碑。在完成这重大的科研项目中,我国科学家所体现的敢做难题、勇攀高峰的精神,顾全大局、团队协作的精神,艰苦奋斗、不计名利的精神和严格认真、严谨求实的精神是值得发扬光大,代代相传的。     

Study of a molybdenum dithiocarboxylato complex. Chemical characterization,crystal and molecular structure of tetrakis(α-dithionaphthoato)molybdenum(IV)

Summary The complex Mo(-C₁₀H₇CS₂)₄ has been prepared from several starting materials: [Mo(NNHPh)₂(butane-2,3-diolate)₂] · H₂NNHPh, [MoCl(NNMe₂)₂(PPh₃)₂]⁺Cl^–, [MoO₂ (MeCHOCHOHMe)₂] · 2MeCHOHCHOHMe or [(C₄H₉)₄N]₆Mo₇O₂₄, reacted with-C₁₀H₇CS₂H. The complex Mo(-C₁₀H₇CS₂)₄ crystallizes from CH₂Cl₂-Et₂O in the orthorhombic space group Pbca,a=13.655(3)Å,b=21.707(5)Å,c= 26.365(2)Å, V=7814.81ų, Z=8; 5075 reflections collected, 2723 used in solution to give R=0.0517, R_w=0.0564. The molybdenum is eight coordinate with geometry approximating to aD _2d dodecahedron. The average Mo-S bond lengths are 2.526(3)Å and 2.479(3)Å for the dodecahedrala andb sites, respectively.     

Enhanced optical limiting performance of a novel molybdenum complex of fullerene

Reverse saturable absorption of a novel molybdenum complex of fullerene (η²-C₆₀) Mo(CO)₂(o-phen)(DBM)·2C₆H₆·C₅H₁₂ has been investigated under irradiation of 10 ns laser pulses at 532 nm. An enhancement of the optical limiting behavior was observed in comparison with C₆₀. An explanation based on the enhanced triplet-state absorption caused by the intra-molecular charge transfer was predicted. The relationship between the clamped laser fluence and low-intensity transmissivity, or the concentration of the solution, was also investigated and a linear dependence was revealed.