CRYSTAL STRUCTURE OF (Et_4N)_2[Mo_6O(μ-O)_(12)O_5]

<正> Mr= 1140.4, tetragonal,P4/mnc,a=10.726(2), c=14.208(3)A, Z=2,Dc=2.316 g.cm-3,V=1634.5(9)A3,final R=0.050 for 1457 independent reflections. The anion [Mo6O19]2- has its No atoas in octahedral configuration with one oxygen atom situated in the center of the octahedron, twelve bridging oxygen atoms,and six terminal oxygen atoms. The average bond lengths of the three types of Mo-O bonds are 1.678 A (Mo=0), 1.919A [Mo-(μ-O)], and 2.310 A [Mo-(μs-O)], respectively.     

CRYSTAL STRUCTURE OF (Et_4N)_3[Mo_2Fe_6S_8(SPH)_9]

<正> Introduction. A series Of Mo-Fe-S complexes with doublecubane structure has been synthesized and identified. Because of the similarity of its extended X-ray absorption fine structure (EXAFS) to that of FeMo cofactor and nitrogenase, suggestion has been made that the doublecubane complexes may serve as models for the Mo site of nitrogenase. Therefore, the investigation of this type of complexes has attracted much attention. By using the similar method of spontaeous self-assembly reaction, and starting from certain kinds of Mo-Fe-S compounds, we have been able to obtain several kinds of compounds, one of which     

SYNTHESIS AND CRYSTAL STRUCTURE OF Mo_2OS(μ-S)_2[S_2CNC_4H_8]_2

Mo_2OS(μ-S)_2[S_2CNC_4H_8]_2, Mr=612.61, triclinic, PI, a=8.666(2)(?), b=17.366(6)(?), c=6.708(1)(?), α=98.29(2)°, β=97.27(2)°, γ=79.36(2)°, V=976.5(5)(?)~3, Z=2, Dc=2.03g/cm~3, MoKα(λ=0.71069(?)), μ=19.75cm~(-1), F(000)=588, Final R=0.064, Rw=0.073 for 1517 unique intensity data (I>3σ(I)). The binuclear unit of [Mo_2OS_3] has a new asymmetrically terminal coordinated configuration with Mo-Mo distance of 2.807(3)(?).     

CRYSTAL STRUCTURE OF (Et_4N)_4[Mo_2Fe_7S_8(SPh)_(12)]

<正> (Et4N)4[Mo2Fe7S8(SPh)12] : Mw=2670.3, triclinic, p1, a=12.775(4), b=13.076(3), c=20.576(4)A, α=80.00(2), β=81.39(2), γ=61.51(2)°, V=2966.3(14) A3, Z=1, D=1.494 gcm-3, R=0.077 for 4031 observed reflections. The complex was prepared by reactions of (Et4N)2[Fe4(SPh) 10] with (Et4N)2MoS4 in an ace-tonitrile solution. The structure of [Mo2Fe7S8(SPh)12]4- anion is a double-cubane-like configuration bridged by a Fe(SPh)6 group.     

CRYSTAL STRUCTURE OF Mo_3(μ3-S)_2(μ-Cl)_3[S_2P(OEt)_2]_3

<正> M=1013.98, hexagonal, P63/m, a=b=15.492(2), c=8.530(4)A, γ=120°, V=1773A3, Z=2, Dc=1.899°g.cm-3. Final R=0.042 for 611 reflections.This is a Bl(bicapped) type trinuclear molybdenum cluster with two S capping atoms located on the 63 axis and exhibits full D3h symmetry. The Mo-Mo distances are 2.606(1)A, with a bond order of 11/3. It is paramagnetic.     

SYNTHESIS AND STRUCTURE OF (Et_4N) [Fe_4S_4 (Et_2NCS_2)_4 ]

<正> INTRODUCTION. The Fe_4S_4 cubane-like clusters have been extensively studied as the model compounds for the active center of the Fe-S proteins in the last fifteen years. Coucouvains et al. have recently reported the syntheses and structures of a few Fe_4S_4 cluster compounds containing R_2NCS_2(R_2dtc) and RS (or Cl) mixed terminal ligands and having [Fe_4S_4]~(2+) core oxi-     

SYNTHESIS AND CRYSTAL STRUCTURE OF A TUNGSTEN-COPPER-SULFUR CLUSTER [Et_4N]_2[WCU_3S_4(S_2CNEt_2)_3]

<正> [Et4N]2 [WCu3S4 (S2CNEt2)3], Mr = 1172. 01, orthorhombic, space group P212121 with a=12. 858(9),b=13. 204(5) ,c=29. 501(9) A ,V=5008. 7 A3, Z = 4, Dc = 1. 55gcm-3, μ(MoKa) = 40. 3cm-1. The final R and Rw are 0. 069 and 0. 075, respectively, for 3072 observed unique reflections. The anion contains a slightly distorted WS42~ tetrahedron coordinated by three CuS2 CNEt2 units,with four metal atoms lying in a plane.     

CRYSTAL STRUCTURE OF {Mo_3(μ_3-S)(μ-S)_3 [S_2P(OEt}_2]_4·PhCH_2CN}

<正> Mr=2548.12, Triclinic, P1, a=15.941(5), b=15.957(2),c=20.240(6)A, α=76.41(2),β=83.87(2),γ=74.41(2)°,V=4814.6A3, Z=4, Dc=1.757g.cm-3, Final R=0.053 for 11867 reflections. There are two crystallographically independent M1 type trinuclear Mo cluster molecules with 'loose coordination site', A and B, in an asymmetric unit of the title crystal. They are formulated as {Mo3S4(u-dtp)(dtp)3.PhCH2CN}(dtp=[S2P(OEt)2]-) and have essentially identical cluster molecular configuration, but differ from each other in the conformations for the phenyl rings of the ligands PhCH2CN. The lengths of the Mo-Mo bonds are 2.750(1), 2.753(1),and 2.768(1)A for molecule A and 2.742(1), 2.756(1), and 2.764(1)A for molecule B, while the dihedral angles betweem the phenyl ring and the {Mo3} triangle are 25.0° and 94.9° for A and B respectively.     

CRYSTAL STRUCTDBE OF H_2(Et_4N)_2[Mo_8O_(26)]

<正> Mr= 1446.02, Monoclinic, P21/n, a = 11.841(2),b= 20.008(6), c= 12.053(8)A,β=105.15(3)°,V= 2756(3)A3,Z= 2, DC = 1.738 g·cm-3. Final R=0.035 for 4326 reflections. The title compound is the decomposition product of the trinuclear Mo cluster anion [Mo3(μ3-O)(μ-Cl)3(μ-OAc)3Cl3]-. The [No8O26]4- anion reported here has the a -type configuration, which consists of a ring made up of six edge-sharing [MoO5] octahedra linked loosely to two [MoO4] units.     

SYNTHESIS AND STRUCTURE OF A TRITHIOCARBONATO Mo(Et_4 N)_2 [(S_2)Mo_2O_2(μ-S)_2(CS_3)]

A new trithiocarbonato Mo complex(Et_4N)_2[(S_2)Mo2O_2(μ-S)_2(CS_3)]was obtained from asystem containing MoO_4~(2-),S_x~(2-),and CS_2 and characterized by IR and X-ray structural analysis.The complex crystallizes in the (?)onoclinic space group P2_1/c with a=9.539(3)(?),b=20.745(2)(?),c=15.452(2)(?),β=94.58(2)°,and Z=4.The structure was solved by direct anddifference Fourier synthesis methods.Least squares refinement using 2910 reflections withI>3σ(I)converged to R=0.054.The CS_3~(2-) iigand in the complex chelates to Mo atom andvalues of the C-S bond distances in the CS_3~(2-) ligend indicate a substantial contribution ofthree resonance forms.     

CRYSTAL STRUCTURE OF Mo_3(μ3-S)(μ-S)_2[S_2P(OEt)_2]_3][SOP(OEt)_2](0)_2

<正> M=1140.85, monoclinic, P21/c. a=12.748(2), b=14.320(2), c=23.118 (3)A,β=101.07(1)°, V=4141(2)A3, Z=4, Dc=1.830 g.cm-3. Final R=0.039 for 4160 reflections.The title compound is a rather irregular trinuclear molybdenum cluster having only two M-M bonds with two shorter Mo-Mo distances of 2.808(1), 2.839(1), and one longer Mo-Mo distance of 3.337(1)8. The existence of two Mo-Mo bonds is coincident with the electron counting for {Mo3} cluster core, and may be regarded as a result of the oxidation of a compound Mo3(μ3-S)(μ-S)2 (μ-L)[S2P(OEt)2]4(L') (L'=neutral ligands)1 characterized by us previously.     

THE CRYSTAL STRUCTURE OF Mo_203[S_2P(OC_2H_5)_2]_4

<正> Introduction. In an attempt to synthesize Mo cluster compounds from the high-valenced Mo compounds in P_2S_5/EtOH-HC1 system we have obtained a brownblack rhombohedral crystal. The composition of it Mo_2O_3[S_2P(OC_2H_5)_2]_4 has been confirmed by X-ray single crystal structure determination, which reveals that the crystal structure is different from that by Knox, J. R. & Prout, C. K. (1969).     

CRYSTAL STRUCTURE OF (Et_4N)2 [Mo_3 (μ_3-O) (μ_3-Cl) (μ-Cl)_3 Cl_6]·EtOH

<正> Mr=963.9, monoclinic, P21/c, a=11.379(3), b=20.766(2), c=14.487(3) A,β=91.49(2)°, V=3518.9A3, Z=4, Dm=1.81, Dx=1.819 g·cm-3, MoKα radiation, λ=0.71073A, μ=18.167, F(000)=1916, T=293 K, R=0.040 for 3261 reflections. The structure consists of two sets of tetraethylammonium cations and trinuclear Mo cluster anions. The cluster skeleton is formed by three Mo atoms arranged in an isosceles triangle with a Cl and an O atoms as capping ligands.     

SYNTHESIS AND STRUCTURE OF A MIXED-VALENCE HEXAMOLYBDENUM COMPLEX [Et_4N]_2[Mo_6O_(19)H_4]

A hexamolybdenum complex, [Et_4N]_2[Mo_6O_(19)H_4] crystal, withpentavalent and hexavalent molybdenum has been obtained in the solution ofDMF and CH_3OH as organic solvents using MoCl_5 as a starting material. Thecrystallographic parameters obtained by X-ray diffraction analysis are:crthorhombic, a=10. 757(3), b=10. 763(2), c=14. 238(4)A, =1648. 9A~3; Z=2; spacegroup Pnnm; final R=0. 047; final Rw=0. 051~(**)     

CRYSTAL STRUCTURE AND REACTIVITY OF (Et_4N) [Mo_3(μ_6-O)-(μ-Cl)_3(μ-OAc)_3Cl_3]

<正> (Et4N)[Mo3(μ3-O)(μ-Cl)3(μ-OAc)3Cl3], C14H29Cl6Mo3NO7, Mr = 823.92, triclinic, P1, a = 17. 508(4), b = 19. 602(3), c=8. 091(2)A, α=91. 25(2)°, β= 96. 56(2)°,γ= 83. 61(2)°, V = 2741(1)A3, Z = 4, Dc = 2.00g/cm3, MoKa (λ=0. 71069A), μ= 19. 44cm-1, F(000) = 1616, T = 23℃, final R = 0. 055, Rw = 0. 068 for 5728 unique intensity data (I≥3σ(I)).The molecule consists of cluster aniorn [Mo3(μ3-O) (μ-Cl)3(μ-OAc)3Cl3]- and cation (Et4N) + . There are two independent molecules in an asymmetric unit whose cluster anions A and B have the same configuration except for some bonding parameters. The cluster core may be described as an equilateral {Mo3} triangle with a capping O atom and three bridging Cl atoms below and above it respectively. In addition, each pair of Mo atoms is bridged by an acetate group and each Mo atom is further coordinated to a terminal chlorine atom. The three Mo - Mo bonds are 2. 587 (2), 2.587(2), 2. 582(2) A for cluster anion A and 2. 587(2), 2.595(2), 2.577 (2) A for cluster a     

SYNTHESIS AND CRYSTAL STRUCTURE OF Mo_3(μ_3-O)(μ-S)_3[S_2P(OEt)_2]_4(C_3H_3N_2)

<正> Mr=1164, space group C2/c, a=14.954(13)A,b=22.323(6)A,c=27.003(18)A,β=98.23(7)°,V=8920 A3, Z=8. Final R=0.069 for 2818 unique diffraction data with I≥30(I). The title cluster compound is of Ml configuration with a triple bridging atom O and with a 'loosely coordinated site' occupied by an imidazole ligand. Three Mo-Mo bond lengths are 2.657 (2), 2.649(2),and 2.646(2)A,respectively. The average bond length of Mo-(μ3-O) bonds is 2.052 A.     

CRYSTAL STRUCTURE OF Mo_3(μ_3-O) (μ-S_2)_ 3 [S_2P(OEt)_2]_3I

<正> Mr=1178.9, monoclinic, P21/n, a=16.570(2), b=12.370(1), c=20.007(2) A,β=99.97(1)°, V=4039.0A3, Z=4, Dx=1.938 Mgm-3, λ(MoKα)=0.7107A, μ(MoKα)=23.96 F(000)=2296, room temperature. Final R value=0.047 for 4387 unique observed reflections. It consists of neutral mono-oxo-capped trinuclear molybdenum cluster molecules with an average Mo-Mo bond length of 2.626(4)A and an average Mo-0 bond length of 2.036(2)8.     

CRYSTAL STRUCTURE OF Mo_2(u-S)_2(S_2P(OEt)_2)_4

<正> Mr=996.91, triclinic, P1, a=8.773(2), b=9.712(3), c=13.652(1) A; α=69.24(0), β=70.43(3), γ=66.87(l)°; Z=l, Dx=1.699 g/cm 3. Final R=0.053 for 3186 reflections with I≥3a(I). There is an interesting trans influence of μ-s bridge in this binuclear cluster. Mo-Mo distance is 2.752(1) A.     

CRYSTAL STRUCTURE OF W_4(μ_(3-)S)_4[S_2P(OEt)_2]_6

<正> W4S4 [S2P (OEt)2]6, Mr= 1974. 94, triclinic, P1, a = 14. 063 (5) , b = 16. 289(4), c= 13. 377(3) A ,α=92. 06 (2), β=95. 24(3), γ= 73. 06(2)°, V= 2919(3)A3,Z=2,DC=2. 18g/cm3, Moka radiation,λ =0. 71069A ,μ = 90. 64cm-1, F(000) = 1764,R=0. 053 and Rw = 0. 069 for 5422 reflections with I≥3σ(I).The title compound is comprised of a cubane-like cluster core [W4S4] in which every W atom is coordinated by six S atoms to form a distorted octahedron.     

SYNTHESIS AND CRYSTAL STRUCTURE OF THE TRI-(μ2-METHOXY)-BRIDGED 'DOUBLE-CUBANE' CLUSTER COMPLEX (Et_4N)_3[Mo_2Fe_6S_8(OMe)_3(SPh)_6]

<正> The title compound was synthesized and crystal structure was solved. (Et4N)3[Mo2Fe6S8(OMe)3(SPh)6], Mr=1922.39, hexagonal, PGs/m, a = 17.750(3), c=15.880(2) A, V=4332.7(26) A3, Z-2, Dx=1.477 g/cm3, MoKα, λ= 0.71069 A, R = 0.059, Rw = 0.065, for 814 observed reflexions. The complex anion contains two Fe3MoS4 cubane-like units linked throug their molybdenum atoms by three ,μ2-methoxy-groups, and the overall structure of the anion has C3b symmetry.