Xuetai Chen

Syntheses and electrochemistry of some transition metal complexes with 2-mercaptopyridine N-oxide and crystal structure of bis(2-mercaptopyridine N-oxide)nickel(II)

Abstract The complexes M(mpo)n (M = Mn, Ni, n = 2; M = Fe, Co, n = 3) (Hmpo = 2-mercaptopyridine N-oxide) were prepared by reacting the appropriate metal chloride with either Nampo or dtpo [2,2-dithiobis(pyridine N-oxide)] in the presence of sodium methoxide. The structure of the complex Ni(mpo)2 was determined by X-ray diffraction. The nickel atom is in a square planar environment of two mpo− ligands in the cis configuration. The four complexes were investigated by physicochemical methods especially by 1H NMR spectroscopy and cyclic voltammetry.

Cobalt complexes with pnicogen (phosphine or pyridine) and thiolato ligands. Syntheses, X-ray crystal structures and spectroscopic characterization

Abstract Mixed pnicogen and thiolato mononuclear cobalt complexes, Co(SR)2(PBun3)2 [R = Ph (1); R = Stolyl-p (2)] and Co(mpo)2L [L = PBun3 (3); L = Py (4)], have been synthesized and studied spectroscopically. The complexes 1 and 2 are tetrahedral, as determined by magnetic susceptibility studies. The structures of 3 and 4 were determined by X-ray diffraction. The cobalt(II) ions in both 3 and 4 are in a square-pyramidal environment with the two trans-oriented mpo ligands in the basal plane and the pnicogen group in the axial position.

A novel asymmetrical phosphine tetracobalt complex ofo-Mercaptophenol: Synthesis, structure, and properties of Co4mp4(Hmp)(PBu 3 n )3 (H2mp=o-Mercaptophenol)

AbstractComplex Co4mp4(Hmp)(PBu3n)3 (1) (H2mp=o-Mercaptophenol) was obtained from the reaction of CoCl2 and H2mp in the presence of PBun3 and NaOMe with restricted oxidation. X-ray crystallographic data: triclinic, space group

Triply bridged (O,O′,S)-binuclear oxomolybdenum(V) complexes containing o-mercaptophenol ligands

P - \overline 1

fac-[Co(C5H4NOS)3].H2O. 1/2CH3OH and fac-[Co(C5H4NOS)3]. 1/3CH3OH

,a=15.657(5) Å,b=20.469(8) Å,c=12.383(3) Å,α=93.59(3)°, β=112.45(2)°, γ=93.65(3)°,V=3648.7 Å3,Z=2,Dc=1.33 g/cm3;R=0.065. The molecule consists of four cobalt atoms unsymmetrically bridged by S or S and O atoms from four of the five mp ligands. The fifth mp is terminally chelated to Co(4) which is in a distorted trigonal bipyramidal geometry, while Co(1)-Co(3) are square pyramidal. Atom Co(2) is bonded to Co(1) and Co(3) (average distance 2.632 Å) with strong interactions while Co(4) is only loosely connected to Co(1) (3.402 Å) and Co(3) (2.956 Å) through oxygen bridges and a hydrogen bond. The different coordination environments O2S2P, S4P, and O4S of the cobalt atoms make the molecule highly asymmetrical. XPS fitting data confirm the difference of the Co atoms. FABMS data indicate the possible fragmentation routes. The complex is paramagnetic with μeff=5.2 μB.

Coordination behaviour of an unsymmetrical dithiolate with transition metals. Syntheses and properties of propane-1,2-dithiolate complexes and structures of [Ph4As]2[Mn2(1,2-pdt)4] and [Ph4P]2[Ni3(1,2-pdt)4]·2MeCN

Abstract The title compound (Et4N)[Mn(MP-MP)2] (1) was obtained by air oxidation of an acetonitrile solution of MnCl2-4H2O and Na2MP. The structure of 1 was determined by single crystal X-ray diffraction methods. Crystal data: C32H36MnNO4S4, monoclinic, P21/c, a = 9.598(3), b = 16.845(3), c = 10.702(3) A, β = 111.20(1)°, V= 1613.1 A3, Z = 2; Mr = 681.84; d x = 1.40g cm−3 F(000) = 712; μ = 6.8cm−1, crystal dimensions 0.40 × 0.20 × 0.20 mm3. The Mn atom is octahedrally and symmetrically coordinated by two MP-MP2- ligands, each providing two phenolate-oxygen and one disulfide-sulfur atoms to form a terdentate. The presence of an S-S bond is revealed by the distance of 2.093 A, which constitutes the first disulphide chelated to the Mn(III) ion. The paramagnetic nature of the high spin Mn(d4) ion is reflected in a value of μcff of 4.83 μB and broad 1H NMR absorptions at 23 ∼ 25ppm and –12∼-17ppm.

Syntheses, structures and properties of tri-n-butylphosphine cobalt complexes containing o-benzenedithiolate ligands in unusual co-ordination modes

Abstract Complexes [A][Mo 2 O 2 (μ-O)mp 3 Na(EtOH) 3 ] (A = Et 4 N (1a); A = nBu 4 N (1b)) and (n-Bu 4 N) [Mo 2 O 2 (μ-OEt)mp 3 ] (2) have been obtained by the reaction of MoOCl 3 (THF) 2 and Na 2 mp (H 2 mp = o -mercaptophenol) in appropriate solvents. Both (1b) and (2) crystallize in monoclinic space group P2 1 /n. Cell parameters for (1b): a = 12.776(3), b = 14.154(5), c = 26.281(7) A, β = 95.50(2)°, V = 4730.5 A 3 , Z = 4, D calc = 1.427 g/cm 3 ; for (2): a = 12.617(5), b = 23.817(18), c = 14.228(7) A, β = 105.79(4)°, V = 4114.1 A 3 , Z = 4, D calc = 1.427 g/cm 3 . The structures were solved by direct methods from 3348 (1b) or 1583 (2) unique reflections with I > 3σ (I) to final convergence factors of R(R w ) 0.070(0.070) for (1b) and 0.090(0.099) for (2). The two [Mo(O)mp] + units are triply bridged by one doubly bridging mp 2− ligand with exceedingly small bite angles (68.85°) and bite distances (2.70 A) and an inorganic oxygen atom for (1b) or an ethoxy group for (2). The molybdenum(V) atoms are in an environment of O 4 S 2 , forming a distorted octahedron with the terminal oxo groups cis to each other. Information concerning the possible origin of oxygen atoms in MoFepr is derived from the structural data of these two complexes. 1 H NMR and CV measurements were also studied.

SYNTHESES, STRUCTURES, AND PROPERTIES OF VANADIUM, COBALT, AND NICKEL COMPOUNDS WITH 2-MERCAPTOPHENOL

Abstract The title complex Mn2 (μ-OCH3)2(MP-MP)2(DMSO)2 1, (MP-MP2- = bis(2-oxyphenyl)disulfide) was obtained by the reaction of Mn(CH3CO2)2.4H2O, H2MP (o-mercaptophenol) and NaOMe in the mixed solvent DMSO/CH3OH. The structure of 1 was determined by X-ray diffraction methods. Crystal data: C30H34Mn2O8S6, triclinic, P 1, a = 8.410(1), b = 8.738(1), c = 12.588 (2)A, a = 82.85(1), β = 85.78(1), y = 72.38(1)°, V = 874.1 A3,Z = 1, Mr = 824.86, dx = 1.57 g/cm3, F(000) = 424, μ (Mo Kα) = 10.8 cm−1, R(Rw ) = 0.057(0.061). The molecule consists of two monomers, Mn(OCH3)(MP-MP)(DMSO), bridged by the methoxide groups. Each MP-MP2- ligand provides two phenolate oxygen atoms and one disulfide sulfur atom to the manganese(III) ion in the Mn2(μ-OMe)2 unit. The effective magnetic moment is μeff = 4.24 μB per Mn(III) ion at room temperature.