Synthesis and reactivity of ruthenium complexes with 1,1′-dithiolate ligands

Reactions of [Ru(PPh₃)₃Cl₂] with ROCS₂K in THF at room temperature and at reflux gave the kinetic products trans-[Ru(PPh₃)₂(S₂COR)₂] (R = ⁿPr 1, ⁱPr 2) and the thermodynamic products cis-[Ru(PPh₃)₂(S₂COR)₂] (R = ⁿPr 3, ⁱPr 4), respectively. Treatment of [RuHCl(CO)(PPh₃)₃] with ROCS₂K in THF afforded [RuH(CO)-(S₂COR)(PPh₃)₂] (R = ⁿPr 5, ⁱPr 6) as the sole isolable products. Reaction of [RuCl₂(PPh₃)₃] with tetramethylthiuram disulfide [Me₂NCS₂]₂ gave a Ru(III) dithiocarbamate complex, [Ru(PPh₃)₂(S₂CNMe₂)Cl₂] (7). This reaction involved oxidation of ruthenium(II) to ruthenium(III) by the disulfide group in [Me₂NCS₂]₂. Treatment of 7 with 1 equiv. of [M(MeCN)₄][ClO₄] (M = Cu, Ag) gave the stable cationic ruthenium(III)-alkyl complexes [Ru{C(NMe₂)QC(NMe₂)S}(S₂CNMe₂)(PPh₃)₂][ClO₄] (Q = O 8, S 9) with ruthenium-carbon bonds. The crystal structures of complexes 1, 2, 4·CH₂Cl₂, 6, 7·2CH₂Cl₂, 8, and 9·2CH₂Cl₂ have been determined by single-crystal X-ray diffraction. The ruthenium atom in each of the above complexes adopts a pseudo-octahedral geometry in an electron-rich sulfur coordination environment. The 1,1′-dithiolate ligands bind to ruthenium with bite S-Ru-S angles in the range of 70.14(4)-71.62(4)°. In 4·CH₂Cl₂, the P-Ru-P angle for the mutually cis PPh₃ ligands is 103.13(3)°, the P-Ru-P angles for other complexes with mutually trans PPh₃ ligands are in the range of 169.41(4)-180.00(6)°. The alkylcarbamate [C(NMe₂)QC(NMe₂)S]⁻ (Q = O, S) ligands in 8 and 9 are planar and bind to the ruthenium centers via the sulfur and carbon atoms from the CS and NC double bonds, respectively. The Ru-C bond lengths are 1.975(5) and 2.018(3) Å for 8 and 9·2CH₂Cl₂, respectively, which are typical for ruthenium(III)-alkyl complexes. Spectroscopic properties along with electrochemistry of all complexes are also reported in the paper.     

A Layered Vanadium Oxide with Cobalt（Ⅱ） Coordination Complex： Hydrothermal Synthesis and Crystal Structure of （py）5Co2（H2O）3[V4O12]

A novel layered mixed metal vanadium-cobadt complex, （py）5Co2（H2O）3[V4O12] 1 （py = pyridine）, was hydro（solvo）thermally synthesized and characterized by single-crystal X-ray diffraction. It crystallizes in orthorhombic, space group Pca21 with a = 17.473（4）, b = 11.447（2）, c = 17.509（4）A^°, V = 5005.3（7）A^°3, Z = 4, Mr = 3502.1（12）, Z = 4, Dc = 1.827 g/cm^3,μ（MoKα） = 2.023 mm^-1, F（000） = 1928, S = 1.020, the final R = 0.0400 and wR= 0.1063 for 6035 observed reflections with I 〉 2σ（I） and 460 variables. Complex 1 consists of tetrahedral VO4 groups to form the large layers which are alternately bonded by two cobalt complex species Co（py）2（H2O）2 and Co（py）3（H2O）.     

Polystyrene/MMT nanocomposites prepared by soap-free emulsion polymerization with high solids content

Polystyrene/montmorillonite (PSt/MMT) nanocomposite latexes have been synthesized by soap-free emulsion polymerization using MMT clay platelets as stabilizer. Small amounts of methacrylic acid were used as auxiliary monomer to promote clay adhesion to the surface of the particles. Overall solids content of the composite latexes in complete absence of coagulation of up to 30.7?wt% are reported under batch conditions. The 3?wt% MMT clay platelets were sufficient to maintain the colloidal stability and increasing MMT clay content resulted in the increase of particle diameter due to the improved viscosity of reaction medium. Transmission electron microscopy results demonstrate the existence of MMT platelets on the particle surface. X-ray diffraction spectroscopy (XRD) results show that an exfoliated structure of PSt/MMT nanocomposites was obtained in this study with the absence of d₀₀₁ diffraction peak of MMT in the XRD region.     

Stable Hydrogen-Bonded Spherical Capsules Formed from Self-Assembly of Pyrogallol[4]arenes

The self-assemblies of two pyrogallol[4]arenes held together by 48 intermolecular hydrogen bonds stably associate in the form of spherical hexameric capsules. The molecular structures of two hexameric capsules with large interior space were analyzed by single crystal X-ray crystallography.     

Molecular structure and nonlinear optical properties of a tetrasilver(I) phosphonitocavitand

A tetrasilver(I) phosphonitocavitand was synthesized and structurally characterized. The compound crystallizes in the monoclinic space group P2₁/n with a=15.0151(13), b=39.832(4), c=15.2479(14) Å, β=95.1000(2)°, V=9083.3(14) Å³ and Z=4. The structure contains four coplanar silver atoms bridged by four μ-Cl and one central trapped μ₄-Cl atoms in the inside of the closing bowl-shaped cavitand. Nonlinear optical properties of this metal-cavitand were investigated. Optical limiting effect with threshold of 0.6 J cm⁻² was observed with the laser pulses of 7 ns at 532 nm.     

Titanium(IV) and zirconium(IV) sulfato complexes containing the Kläui tripodal ligand: molecular models of sulfated metal oxide surfaces

Treatment of titanyl sulfate in about 60 mM sulfuric acid with NaL(OEt) (L(OEt) (-)=[(eta(5)-C(5)H(5))Co{P(O)(OEt)(2)}(3)](-)) afforded the mu-sulfato complex [(L(OEt)Ti)(2)(mu-O)(2)(mu-SO(4))] (2). In more concentrated sulfuric acid (>1 M), the same reaction yielded the di-mu-sulfato complex [(L(OEt)Ti)(2)(mu-O)(mu-SO(4))(2)] (3). Reaction of 2 with HOTf (OTf=triflate, CF(3)SO(3)) gave the tris(triflato) complex [L(OEt)Ti(OTf)(3)] (4), whereas treatment of 2 with Ag(OTf) in CH(2)Cl(2) afforded the sulfato-capped trinuclear complex [{(L(OEt))(3)Ti(3)(mu-O)(3)}(mu(3)-SO(4)){Ag(OTf)}][OTf] (5), in which the Ag(OTf) moiety binds to a mu-oxo group in the Ti(3)(mu-O)(3) core. Reaction of 2 in H(2)O with Ba(NO(3))(2) afforded the tetranuclear complex (L(OEt))(4)Ti(4)(mu-O)(6) (6). Treatment of 2 with [{Rh(cod)Cl}(2)] (cod=1,5-cyclooctadiene), [Re(CO)(5)Cl], and [Ru(tBu(2)bpy)(PPh(3))(2)Cl(2)] (tBu(2)bpy=4,4'-di-tert-butyl-2,2'-dipyridyl) in the presence of Ag(OTf) afforded the heterometallic complexes [(L(OEt))(2)Ti(2)(O)(2)(SO(4)){Rh(cod)}(2)][OTf](2) (7), [(L(OEt))(2)Ti(O)(2)(SO(4)){Re(CO)(3)}][OTf] (8), and [{(L(OEt))(2)Ti(2)(mu-O)}(mu(3)-SO(4))(mu-O)(2){Ru(PPh(3))(tBu(2)bpy)}][OTf](2) (9), respectively. Complex 9 is paramagnetic with a measured magnetic moment of about 2.4 mu(B). Treatment of zirconyl nitrate with NaL(OEt) in 3.5 M sulfuric acid afforded [(L(OEt))(2)Zr(NO(3))][L(OEt)Zr(SO(4))(NO(3))] (10). Reaction of ZrCl(4) in 1.8 M sulfuric acid with NaL(OEt) in the presence Na(2)SO(4) gave the mu-sulfato-bridged complex [L(OEt)Zr(SO(4))(H(2)O)](2)(mu-SO(4)) (11). Treatment of 11 with triflic acid afforded [(L(OEt))(2)Zr][OTf](2) (12), whereas reaction of 11 with Ag(OTf) afforded a mixture of 12 and trinuclear [{L(OEt)Zr(SO(4))(H(2)O)}(3)(mu(3)-SO(4))][OTf] (13). The Zr(IV) triflato complex [L(OEt)Zr(OTf)(3)] (14) was prepared by reaction of L(OEt)ZrF(3) with Me(3)SiOTf. Complexes 4 and 14 can catalyze the Diels-Alder reaction of 1,3-cyclohexadiene with acrolein in good selectivity. Complexes 2-5, 9-11, and 13 have been characterized by X-ray crystallography.     

超声条件下合成4—戊基（4‘—丙基）双环己基联苯

在超声辐射下,用相转移催化剂十六烷基三甲基溴化铵作助催化剂,室温下通过氯化钯催化４－（４’－丙基）环己基苯基硼酸与４－（４’－戊基）环己基溴苯偶联反应２０ｍｉｎ,合成了４－戊基（４’－丙基）双环己基联苯,反应转化率９７％,反式产物选择性６２％。     

Phase Transition Kinetics in Bi3NbO7 Evaluated by in situ Isothermal Conductivity Measurements

Kinetics of phase transformation from pseudocubic to tetragonal phase in Bi3NbO7 solid solution is studied by using the ac impedance method under isothermal conditions. Conductivity of the investigated compound is used to characterize the kinetic process of the transition. The Avrami exponent and the activation energy of phase transition are around 1.5 and 3.5eV, respectively. These kinetic parameters reveal that the pseudocubic-tetragonal transition in Bi3NbO7 .belongs to a three-dimensional diffusion-controlled growth with zero nucleation rate.     

Methods,Syntheses and Characterization of Diaryl,Aryl Benzyl,and Dibenzyl Sulfides

Twenty-four aryl benzyl sulfides, diaryl sulfides and dibenzyl sulfides were synthesized by four methods and characterized by ¹H NMR, FT-IR and Gas chromatography. The reaction conditions of different synthesis methods were studied from the aspects of time, solvent, base and dispersant. The molecular structures of benzylphenyl sulfide (2S), (4-tert-butylbenzyl)(4-methylphenyl) sulfide (4S), (4-methylbenzyl)(4-methylphenyl) sulfide (9S), di(4-methylphenyl) sulfide (11S), (3,5-dimethylphenyl)(4-methyl phenyl) sulfide (15S), and dibenzyl sulfide (19S) [22] have been determined by single-crystal X-ray crystallography. Compounds 2S and 15S crystallize in the monoclinic space group P2₁/c, with a?=?12.278(3), b?=?15.894(3), c?=?5.6056(11) Å, β?=?94.532(2)°, and Z?=?4 for 2S, and a?=?9.800(9), b?=?7.950(7), c?=?16.690(15) Å, β?=?100.890(12)°, and Z?=?4 for 15S. The unit cell of 4S has a triclinic Pī symmetry with the cell parameters a?=?6.0436(10), b?=?8.7871(14), c?=?15.535(2) Å, α?=?81.921(2)°, β?=?81.977(2)°, γ?=?80.889(2)°, and Z?=?2. Compounds 9S and 11S both crystallize in the orthorhombic space group P2₁2₁2₁, with a?=?6.188(3), b?=?8.041(4), c?=?26.005(14) Å, and Z?=?4 for 9S, and a?=?5.835(2), b?=?8.010(3), c?=?25.131(9) Å, and Z?=?4 for 11S.

Graphic Abstract

Twenty-four aryl sulfide compounds with different substituents were synthesized and characterized, and the molecular structures of six different sulfide compounds have been determined by single-crystal X-ray crystallography.