Alternativ-Liganden. XXVI [1]. M(CO)4L-Komplexe (M  Cr,Mo, W) der Chelatliganden Me2ESiMe2(CH2)2E′Me2 (Me  CH3; E  P,As; E′  N,P, As)

Alternative Ligands. XXVI. M(CO)₄ L-Complexes (M ? Cr, Mo, W) of the Chelating Ligands Me₂ESiMe₂(CH₂)₂E′ Me₂ (Me ? CH₃; E ? P, As; E′ ? N, P, As) The reaction of M(CO)₄NBD (NBD = norbornadiene; M ? Cr, Mo, W) with the ligands Me₂ESiMe₂(CH₂)₂E′ Me₂ yields the chelate complexes (CO)₄M[Me₂ESiMe₂]) for E,E′ ? P, As, but not for E and /or E′ ? N. The NSi group is not suited for coordination because of strong (p-d)π-interaction. In the case of the ligands with E ? P or As and E′ ? N chelate complexes can be detected in the reaction mixture, but isolable products are complexes with two ligands coordinated via the E donor group. The new compounds are characterized by analytical and spectroscopic (IR, NMR, MS) investigations. The spectroscopic data are also used to deduce the coordinating properties of the ligands. X-ray diffraction studies of the molybdenum complexes (CO)₄Mo[Me₂ESiMe₂(CH₂)₂AsMe ₂] (E ? P, As) in accord with the observed coordination effects show only small differences between SiE and CE donor functions. Attempts to use the ligands Me₂ESiMe₂(CH₂)₂AsMe₂ (E ? P, As) for the preparation of Fe(CO)₃L complexes result in the fission of the SiE bonds and the formation of the binuclear systems Fe₂(CO)₆(EMe₂)₂ (E ? P, As) together with the disilane derivative [Me₂Si(CH₂)₂AsMe₂]₂.     

[Co4P2(PtBu2)2(CO)8] und [{Co(CO)3}2P4tBu4] aus Co2(CO)8 und tBu2P–P=P(Me)tBu2

Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XIX. [Co₄P₂(P^tBu₂)₂(CO)₈] and [{Co(CO)₃}₂P₄^tBu₄] from Co₂(CO)₈ and ^tBu₂P–P=P(Me)^tBu₂ Co₂(CO)₈ reacts with ^tBu₂P–P=P(Me)^tBu₂ yielding the compounds [Co₄P₂(P^tBu₂)₂(CO)₈] ( 1 ) and [{η^2tBu₂P=P–P=P^tBu₂}{Co(CO)₃}₂] ( 2 a ) cis, ( 2 b ) trans. In 1 , four Co and two P atoms form a tetragonal bipyramid, in which two adjacent Co atoms are μ₂‐bridged by ^tBu₂P groups. Additionally, two CO groups are linked to each Co atom. In 2 a and 2 b , each of the Co(CO)₃ units is η²‐coordinated to the terminal P₂ units resulting in the cis‐ and trans‐configurations 2 a and 2 b . 1 crystallizes in the orthorhombic space group Pnnm (No. 58) with a = 879,41(5), b = 1199,11(8), c = 1773,65(11) pm. 2 a crystallizes in the monoclinic space group P2₁/n (No. 14) with a = 875,97(5), b = 1625,36(11), c = 2117,86(12) pm, β = 91,714(7)°. 2 b crystallizes in the triclinic space group P 1 (No. 2) with a = 812,00(10), b = 843,40(10), c = 1179,3(2) pm, α = 100,92(2)°, β = 102,31(2)°, γ = 102,25(2)°.     

Neue Phosphor-verbrückte Übergangsmetallcarbonyl-Komplexe Die Kristallstrukturen von [Re2(CO)7(PtBu)3], [Co4(CO)10(PtBu)2], [Ir4(CO)6(PtBu)6] und [Ni4(CO)10(PiPr)6]

New Phosphorus-bridged Transition Metal Carbonyl Complexes. The Crystal Structures of [Re₂(CO)₇(P^tBu)₃], [Co₄(CO)₁₀(P^tBu)₂], [Ir₄(CO)₆(P^tBu)₆], and [Ni₄(CO)₁₀(PⁱPr)₆], (P^tBu)₃ reacts with [Mn₂(CO)₁₀], [Re₂(CO)₁₀], [Co₂(CO)₈] and [Ir₄(CO)₁₂] to form the multinuclear complexes [M₂(CO)₇(P^tBu)₃] (M = Re ( 1 ), Mn ( 5 )), [Co₄(CO)₁₀(P^tBu)₂] ( 2 ) and [Ir₄(CO)₆(P^tBu)₆] ( 3 ). The reaction of (PⁱPr)₃ with [Ni(CO)₄] leads to the tetranuclear cluster [Ni₄(CO)₁₀(PⁱPr)₆] ( 4 ). The complex structures were obtained by X-ray single crystal structure analysis: ( 1 : space group P1 (Nr. 2), Z = 2, a = 917.8(3) pm, b = 926.4(3) pm, c = 1 705.6(7) pm, α = 79.75(3)°, β = 85.21(3)°, γ = 66.33(2)°; 2 : space group C2/c (Nr. 15), Z = 4, a = 1 347.7(6) pm, b = 1 032.0(3) pm, c = 1 935.6(8) pm, β = 105.67(2)°; 3 : space group P1 (Nr. 2), Z = 4, a = 1 096.7(4)pm, b = 1 889.8(10)pm, c = 2 485.1(12) pm, α = 75.79(3)°, β = 84.29(3)°, γ = 74.96(3)°; 4 : space group P2₁/c (Nr. 14), Z = 4, a = 2 002.8(5) pm, b = 1 137.2(8) pm, c = 1 872.5(5) pm, β = 95.52(2)°).     

Conformational Rigidity in Complexes [MCl(tBu2PH)3] (M = Rh,Ir)

Reactions of [{M(μ‐Cl)(coe)₂}₂] (M = Rh, Ir; coe = cis‐cyclooctene) with the secondary phosphane tBu₂PH under various molar ratios were investigated. Probably, for kinetic reasons, the reaction behavior of the rhodium species differed from that of the iridium analogue in some instances. During these studies complexes [MCl(tBu₂PH)₃] [M = Rh ( 1 ), Ir ( 2 )] were isolated, and solution variable‐temperature ³¹P{¹H} NMR studies revealed that these complexes show a conformational rigidity on the NMR time scale. Spectra recorded in the temperature range from 173 to 373 K indicated in each case only one rotamer containing three chemically nonequivalent phosphanes due to the restricted rotation of these ligands about the M–P bonds and the tert‐butyl substituents around the P–C(tBu) bonds, respectively. Compound 1 showed in solution already at room temperature in several solvents a dissociation of a phosphane ligand affording the known complex [{Rh(μ‐Cl)(tBu₂PH)₂}₂] beside the free phosphane. In contrast to these findings, the iridium analogue 2 remained completely unchanged under similar conditions and exhibited, therefore, some kinetic inertness. For a better understanding of the NMR spectroscopic investigations, the molecular structure of 1 in the solid state was confirmed by X‐ray crystallography.     

Synthese und Struktur der Phosphor-verbrückten Übergangsmetallkomplexe [Fe2(CO)6(PR)6] (R = tBu,iPr), [Fe2(CO)4(PiPr)6], [Fe2(CO)3Cl2(PtBu)5], [Co4(CO)10(PiPr)3], [Ni5(CO)10(PiPr)6] und [Ir4(C8H12)4Cl2(PPh)4]

Synthesis and Structure of the Phosphorus-bridged Transition Metal Complexes [Fe₂(CO)₆(PR)₆] (R = ^tBu, ⁱPr), [Fe₂(CO)₄(PⁱPr)₆], [Fe₂(CO)₃Cl₂(P^tBu)₅], [Co₄(CO)₁₀(PⁱPr)₃], [Ni₅(CO)₁₀(PⁱPr)₆], and [Ir₄(C₈H₁₂)₄Cl₂(PPh)₄] (P^tBu)₃ and (PⁱPr)₃ react with [Fe₂(CO)₉] to form the dinuclear complexes [Fe₂(CO)₆(PR)₆] (R = ^tBu: 1 ; ⁱPr: 2 ). 2 is also formed besides [Fe₂(CO)₄(PⁱPr)₆] ( 3 ) in the reaction of [Fe(CO)₅] with (PⁱPr)₃. When PⁱPr(P^tBu)₂ and PⁱPrCl₂ are allowed to react with [Fe₂(CO)₉] it is possible to isolate [Fe₂(CO)₃Cl₂(P^tBu)₅] ( 4 ). The reactions of (PⁱPr)₃ with [Co₂(CO)₈] and [Ni(CO)₄] lead to the tetra- and pentanuclear clusters [Co₄(CO)₁₀(PⁱPr)₃] ( 5 ), [Ni₄(CO)₁₀(PⁱPr)₆] [2] and [Ni₅(CO)₁₀(PⁱPr)₆] ( 6 ). Finally the reaction of [Ir(C₈H₁₂)Cl]₂ with K₂(PPh)₄ leads to the complex [Ir₄(C₈H₁₂)₄Cl₂(PPh)₄] ( 7 ). The structures of 1–7 were obtained by X-ray single crystal structure analysis (1: space group P2₁/c (Nr. 14), Z = 8, a = 1 758.8(16) pm, b = 3 625.6(18) pm, c = 1 202.7(7) pm, β = 90.07(3)°; 2 : space group P1 (Nr. 2), Z = 1, a = 880.0(2) pm, b = 932.3(3) pm, c = 1 073.7(2) pm, α = 79.07(2)°, β = 86.93(2)°, γ = 72.23(2)°; 3 : space group Pbca (Nr. 61), Z = 8, a = 952.6(8) pm, b = 1 787.6(12) pm, c = 3 697.2(30) pm; 4 : space group P2₁/n (Nr. 14), Z = 4, a = 968.0(4) pm, b = 3 362.5(15) pm, c = 1 051.6(3) pm, β = 109.71(2)°; 5 : space group P2₁/n (Nr. 14), Z = 4, a = 1 040.7(5) pm, b = 1 686.0(5) pm, c = 1 567.7(9) pm, β = 93.88(4)°; 6 : space group Pbca (Nr. 61), Z = 8, a = 1 904.1(8) pm, b = 1 959.9(8) pm, c = 2 309.7(9) pm. 7 : space group P1 (Nr. 2), Z = 2, a = 1 374.4(7) pm, b = 1 476.0(8) pm, c = 1 653.2(9) pm, α = 83.87(4)°, β = 88.76(4)°, γ = 88.28(4)°).     

Die Reaktion von tBu2P‐P=P(Me)tBu2 mit [Fe2(CO)9] und [(η2‐C8H14)2Fe(CO)3]

^tBu₂P‐P=P(Me)^tBu₂ reacts with [Fe₂(CO)₉] to give [μ‐(1, 2, 3:4‐η‐^tBu₂P¹‐P²‐P³‐P^4tBu₂){Fe(CO)₃}{Fe(CO)₄}] ( 1 ) and [trans‐(^tBu₂MeP)₂Fe(CO)₃]( 2 ). With [(η²‐C₈H₁₄)₂Fe(CO)₃] in addition to [μ‐(1, 2, 3:4‐η‐^tBu₂P¹‐P²‐P³‐P^4tBu₂){Fe(CO)₂PMe^tBu₂}‐{Fe(CO)₄}] ( 10 ) and 2 also [(μ‐P^tBu₂){μ‐P‐Fe(CO)₃‐PMe^tBu₂}‐{Fe(CO)₃}₂(Fe‐Fe)]( 9 ) is formed. 1 crystallizes in the monoclinic space group P2₁/c with a = 875.0(2), b = 1073.2(2), c = 3162.6(6) pm and β = 94.64(3)?. 2 crystallizes in the monoclinic space group P2₁/c with a = 1643.4(7), b = 1240.29(6), c = 2667.0(5) pm and β = 97.42(2)?. 9 crystallizes in the monoclinic space group P2₁/n with a = 1407.5(5), b = 1649.7(5), c = 1557.9(16) pm and β = 112.87(2)?.     

[Ph4P][(C5H6N3O3)M(CO)5] (M = Cr,Mo, W; C5H7N3O3 = 1,3‐Dimethyl‐cyanuric Acid). Organometallic Complexes of the 1,3‐Dimethylcyanurate Ligand

1,3‐Dimethylcyanuric acid (DMCH) forms on deprotonation and reaction with TlF its thallous salt Tl[DCM] ( 2 ) which is converted to the phosphonium salt [PPh₄][DCM] ( 3 ). On the reaction with M(CO)₆, the pentacarbonylmetalate salts [Ph₄P][(DMC)M(CO)₅], M = Cr ( 4a ), Mo ( 4b ) and W ( 4c ) are obtained. IR and NMR data of 4 reveal the DMC anion ( 1 ) to have coordination properties similar to those of pyridine. The crystal structures of 4a and 4c are reported.     

Synthesis and Structure of Dinuclear Molybdenum Carbonyl Thiolate Compound [Et4N ] 2 [Mo2 (CO) 8 (SC6H4-OCH3-p) 2]

Reaction of Mo(CO)6 with p-H3CO-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum(0) compound [Et4N]2[Mo2 (CO)8 (SC6H4-OCH3-p)2] (1). The crystal structure was determined by X-ray diffraction. The crystallographic data: C38H54Mo2N2O10S2, Mr = 954.87, triclinic, P-1, a = 11.348 (7), b =11.616(5), c=10.065(7) A, a=113.86(4), β=111.39(5), γ=91.92(5)°, V=1104.0(1) A3, Z=1, Dc=1.44 g/cm3, F(000)=492, μ=7.0cm-1, Final R=0. 046 and Rw=0. 049 for 2657 reflections with I＞3. Oσ(I). The X-ray structure analysis revealed that the Mo2S2 core of 1 is planar. The geometry around each Mo atom is a distorted octahedron, the two octahedrons form an edge-sharing bioctahedron. The bond. In addition, the 95Mo NMR chemical shift of 1 is discussed.     

Monosubstituted Trinuclear and Tetranuclear VIB Metal Carbonyl Complexes: Syntheses of [{M(CO)5}3(Pf-Pf-Pf)] [Pf-Pf-Pf = PhP(CH2CH2PPh2)2] and [{M(CO)5}4(P-Pf3)] [P-Pf3 = P(CH2CH2PPh2)3] (M = Cr,Mo) and Crystal Structures of the Latter Three

The triligate trimetallic complexes, [{M(CO)₅}₃(Pf-Pf-Pf)] and tetraligate tetrametallic complexes, [{M(CO)₅}₄(P-Pf₃)] (M = Cr and Mo), were prepared from [M(CO) ₆] and the corresponding ligands in MeCN/CH₂Cl₂ promoted by Me₃NO at 0 °C. Crystals of trimer lb are monoclinic, space group P 2₁/n, with a = 13.407(3), b = 15.002(5), c = 26.52(1) Å, β = 90.65(2)°, Z = 4, and R = 0.060 for 2760 observed reflections. Crystals of tetramer 2a are monoclinic, space group P 2₁/c, with a – 14.183(8), b = 29.880(4), c = 16.103(2) Å, β = 94.98(3)°, Z = 4, and R = 0.039 for 5014 observed reflections. Crystals of 2b are monoclinic, space group C 2/c, with a = 42.120(8), b = 13.679(1), c = 23.486(2) Å, β = 92.14(1)°, Z = 8, and R = 0.032 for 6897 observed reflections. Each phosphorus atom of the ligands is coordinated to the M(CO)₅ moiety in each title compounds. The geometry of the four metals is a distorted tetrahedron for the tetramers.     

Neue arsinidenverbrückte Mehrkern-Clusterkomplexe des Ag und Au. Die Kristallstrukturen von [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3, PMenPr2, PnPr3), [M4(As4Ph4)2(PR3)4], (M = Ag,PR3 = PEt3, PnPr3; M = Au,PR3 = PnPr3), [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6]

New Arsinidene-bridged Multinuclear Cluster Complexes of Ag and Au. The Crystal Structures of [Ag₁₄(AsPh)₆Cl₂(PR₃)₈], (PR₃ = PEt₃, PMeⁿPr₂, PⁿPr₃), [M₄(As₄Ph₄)₂(PR₃)₄], (M = Ag, PR₃ = PEt₃, PⁿPr₃; M = Au, PR₃ = PⁿPr₃), [Au₁₀(AsPh)₄(PhAsSiMe₃)₂(PⁿPr₃)₆] The reaction of AgCl with PhAs(SiMe₃)₂ in presence of tertiary phosphines (PR₃) leads to arsinidene-bridged silver clusters with the composition [Ag₁₄(AsPh)₆Cl₂(PR₃)₈], (PR₃ = PEt₃ 1 , PMeⁿPr₂ 2 , PⁿPr₃ 3 ). Further it is possible to obtain the multinuclear complexes [Ag₄(As₄Ph₄)₂(PR₃)₄], (PR₃ = PEt₃ 4 , PMeⁿPr₂ 5 ). In analogy to that [PMe₃AuCl] reacts with PhAs(SiMe₃)₂ and PⁿPr₃ to form the compound [Au₄(As₄Ph₄)₂(PⁿPr₃)₄] 6 , which is isostructurell to 4 and 5 . The gold cluster [Au₁₀(AsPh)₄(PhAsSiMe₃)₂(PⁿPr₃)₆] 7 was obtained from the same solution. The structures were characterized by X-ray single crystal structure analysis. (Crystallographic data see “Inhaltsübersicht”)     

Diphosphine Compounds,Part III: UV/Visible Spectroscopy and Novel Routes to Functionalized Diphosphine-M(CO)6 Complexes (M = W,Mo, or Cr)

Reaction of coordinated (diphenylphosphino)methane and ketones or aldehydes have been characterized by ³¹P{H¹}-NMR, ¹H{³¹P}-NMR, and UV/vis spectroscopy in dichloromethane. Group VI metals hexacarbonyl [M(CO)₆ where M = Cr, Mo, and W] reacted with (diphenylphosphino)methane, [(Ph₂P)₂CH₂], to give [(OC)₄M{(Ph₂P)₂CH₂}] depending upon the reaction conditions. Condensation of [(CO)₄M{(Ph₂P)₂CH₂}] with different ketones or aldehydes forms [(CO)₄M{(Ph₂P)₂C = CR₁R₂}]. Complexes of the types [(OC)₄M{(Ph₂P)₂C = CR₁R₂}] reacted with hydrazine in a Michael addition to give [(CO)₄M{(Ph₂P)₂CHC(R₁R₂)NHNH₂}](1.3a–e), which condensed with different ketones and aldehydes to give complex of the type [(CO)₄M{(Ph₂P)₂CHC(R₁R₂)NHN = C(R₃)] (1.4a–e). The structures of the complexes are discussed on the basis of elemental analysis (EA), IR,¹H-NMR, ³¹P-NMR spectroscopic data, and FAB mass spectra. The UV/vis spectra show two absorption bands with the low energy band moving to lower energy with increasing substitution on the (diphenylphosphino) methane (dppm) (a bathochromic effect).     

Reactions with Oleum under Harsh Conditions: Characterization of the Unique [M(S2O7)3]2− Ions (M=Si,Ge, Sn) in A2[M(S2O7)3] (A=NH4, Ag)

The reactions of group 14 tetrachlorides MCl₄ (M=Si, Ge, Sn) with oleum (65 % SO₃) at elevated temperatures lead to the unique complex ions [M(S₂O₇)₃]^2?, which show the central M atoms in coordination with three chelating S₂O₇^2? groups. The mean distances M? O within the anions increase from 175.6(2)–177.5(2) pm (M=Si) to 186.4(4)–187.7(4) pm (M=Ge) to 201.9(2)–203.5(2) pm (M=Sn). These distances are reproduced well by DFT calculations. The same calculations show an increasing positive charge for the central M atom in the row Si, Ge, Sn, which can be interpreted as the decreasing covalency of the M? O bonds. For the silicon compound (NH₄)₂[Si(S₂O₇)₃], ²⁹Si solid‐state NMR measurements have been performed, with the results showing a signal at ?215.5 ppm for (NH₄)₂[Si(S₂O₇)₃], which is in very good agreement with theoretical estimations. In addition, the vibrational modes within the [MO₆] skeleton have been monitored by Raman spectroscopy for selected examples, and are well reproduced by theory. The charge balance for the [M(S₂O₇)₃]^2? ions is achieved by monovalent A⁺ counter ions (A=NH₄, Ag), which are implemented in the syntheses in the form of their sulfates. The sizes of the A⁺ ions, that is, their coordination requirements, cause the crystallographic differences in the crystal structures, although the complex [M(S₂O₇)₃]^2? ions remain essentially unaffected with the different A⁺ ions. Furthermore, the nature of the A⁺ ions influences the thermal behavior of the compounds, which has been monitored for selected examples by thermogravimetric differential thermal analysis (DTA/TG) and XRD measurements.     

Transition Metal Complexes with more than one Dihydrogen Ligand: Structure and Bonding of M(CO)6–x(H2)x (M = Cr,Mo, W; x = 1, 2, 3) [1]

Quantum mechanical ab initio calculations at the MP2 and CCSD(T) level of theory have been used to investigate the geometries and bond energies of the complexes M(CO)_6–x(H₂)_x (M = Cr, Mo, W; x = 1, 2, 3). The theoretically predicted M(CO)₅–(H₂) bond dissociation energies are in excellent agreement with experimental values. The M–(H₂) dissociation energies of the bis- and tris-dihydrogen complexes are very similar to the values for the mono-dihydrogen complexes. In M(CO)₅(H₂) the dihydrogen ligand prefers an eclipsed conformation relative to the equatorial carbonyl groups. For M(CO)₄(H₂)₂ the cis and trans isomers are nearly equal in energy for M = W, while a cis configuration is favoured for M = Cr. For M(CO)₃(H₂)₃ the facial configurations are more stable than the meridial structures for all three metals M. The charge decomposition analysis (CDA) classifies dihydrogen as a donor ligand with moderate acceptor properties. In trans-M(CO)₄(H₂)₂ back donation is increased and the M–(H₂) bonds are stronger than in M(CO)₅–(H₂). Back donation in M(CO)₃(H₂)₃ is slightly weaker than in the mono-dihydrogen complexes M(CO)₅(H₂).     

Phosphido- und arsenido-verbrückte Zweikernkomplexe: Synthese und Struktur von (η5-C5H4R)2Zr{μ-P(SiMe3)2}2M(CO)4 (R = Me,M = Cr; R = H,M = Mo) sowie die Synthese von (η5-C5H5)2Zr{μ-As(SiMe3)2}2Cr(CO)4

Phosphido- and Arsenido-bridged Dinuclear Complexes. Synthesis and Molecular Structure of (η⁵-C₅H₄R)₂Zr{μ-P(SiMe₃)₂}₂M(CO)₄ (R = Me, M = Cr; R = H, M = Mo) and Synthesis of (η⁵-C₅H₅)₂Zr{μ-As(SiMe₃)₂}₂Cr(CO)₄ The reaction of (η⁵-C₅H₄R)₂Zr{E(SiMe₃)₂}₂ with M(CO)₄(NBD) (NBD = norbornadiene) yields the dinuclear phosphido- or arsenido-bridged complexes (η⁵-C₅H₄R)₂Zr{μ-E(SiMe₃)₂}₂M(CO)₄ (R = Me, E = P, M = Cr ( 1 ); R = H, E = P, M = Mo ( 2 ); R = H, E = As, M = Cr ( 3 )). No formation of dinuclear complexes was observed in the reaction of (η⁵-C₅H₄Me)₂Zr{P(SiMe₃)₂}₂ with Ni(PEt₃)₄, Ni(CO)₂(PPh₃)₂ or with NiCl₂(PPh₃)₂ in the presence of Mg. Complexes 1 – 3 were characterised spectroscopically (i. r., n. m. r., m. s.), and X-ray structure investigations were carried out on 1 and 2 . The central four-membered ZrP₂M ring is slightly puckered (dihedral angle between planes ZrP₂/CrP₂ 14.7°, ZrP₂/MoP₂ 14.2°). The Zr? P bond lengths are equivalent ( 1 : Zr? P1 2.654(4), Zr? P2 2.657(4) Å; 2 : Zr? P1 2.6711(9), Zr? P2 2.6585(7) Å), as are the M? P bond lengths (M = Cr ( 1 ): Cr? P1 2.513(4), Cr? P2 2.502(4) Å; M = Mo ( 2 ): Mo? P1 2.6263(7), Mo? P2 2.6311(10) Å). The long Zr ··· M distances of 3.414 Å (M = Cr ( 1 )) and 3.461 Å (M = Mo ( 2 )) indicate the absence of a metal-metal bond.     

Supramolecular Complexes Based on [M(CN)8]4– (M = Mo,W) and Aliphatic Amine CuII Tectons

Three heterometallic supramolecular complexes [Cu₂(pn)₄(Mo(CN)₈)·4H₂O] (pn = diaminopropane) ( 1 ), [Cu₂(pn)₄(W(CN)₈)·4H₂O] ( 2 ) and [Cu₂(1,2‐pn)₄(H₂O) (W(CN)₈)·3H₂O] ( 3 ) have been synthesized and structurally characterized by single‐crystal X‐ray diffraction studies. Complexes 1 – 3 exhibit three different networks. In 1 , the copper(II) ion is pentacoordinate with a distorted square‐pyramidal arrangement and the network is formed by the incorporation of coordinative linkage between the μ₂ bridge of [Mo(CN)₈]^4– and copper(II) ions and hydrogen‐bonding interactions. In 2 , the copper(II) ion exhibits a distorted square‐pyramidal arrangement and the network is formed by the hydrogen bonded trinuclear complexesof [Cu₂(pn)₂(W(CN)₈)]. In 3 , the copper(II) ions show twodifferent distorted octahedral arrangements. The network structure of 3 is formed by the hydrogen‐bonded complex chains of [Cu₂(1,2‐pn)₂(W(CN)₈)].     

Crystal structure of trans-pyH[MoBr4py2] and reactivity of Trans-pyH[MBr4py2] (M = Mo,W; py = pyridine) towards nitrogen ligands and bromine Oxidation

The crystal structure of trans-pyH[MoBr₄py₂] has been determined: orthorhombic, Pnma (No. 62), a = 16.197(3), b = 13.995(3), c = 8.615(1) Å, Z = 4, D_c = 2.23, D_o = 2.20(3) g/cm³, V = 1 953(1) ų. R₁, R_w = 0.057 and 0.053. Trans-[MoBr₄py₂]^? anions with staggered conformation of pyridine rings are located on the mirror planes. Mo? Br, Mo? N(pyridine) distances are 2.593(1), 2.573(1), 2.227(8) and 2.213(7) Å. Cations are located on the symmetry centers. The cation in trans-pyH[MBr₄py₂] can be replaced. Trans-NH₄[MBr₄py₂] · H₂O, Cs[MBr₄py₂], LH[MBr₄py₂] (M = Mo, W; L = 4-methylpyridine, 4-pic; 2,2′-bipyridyl, bipy) were prepared. The compounds of molybdenum and tungsten with the same chemical composition are isostructural. All compounds react with pyridine and 4-methylpyridine. The products are trans-MBr₃L₃, and in the case of molybdenum, also trans-MoBr₃py₂(4-pic). Bromine oxidizes trans-M^I[MBr₄py₂] to trans-MBr₄py₂.     

[M(en)3] (ndt)•H2O的水热合成、晶体结构和光学性能 ( M=NiⅡ, CoⅡ, MnⅡ and ndt=1,5-naphthalenedithiolate )

水热条件下，合成了三个新的配合物[Ni(en)₃] (ndt) ·H₂O 1, [Co(en)₃] (ndt) ·H₂O 2 和[Mn(en)₃] (ndt) ·H₂O 3。晶体结构通过X-射线单晶衍射进行了表征。三个配合物均属于单斜晶系，Cc空间群。[M(en)₃]²⁺阳离子、ndt阴离子和结晶水分子通过氢键自组装出相同结构的三维网。通过紫外-可见-近红外漫反射光谱对这三个配合物的光吸收性能和能带进行了测定。     

Tri(1-cyclohepta-2,4,6-trienyl)phosphan,P(C7H7)3 und Tetra(1-cyclohepta-2,4,6-trienyl)phosphonium-tetrafluoroborat, [P(C7H7)4]BF4

Tri(1-cyclohepta-2,4,6-trienyl)phosphane, P(C₇H₇)₃, and Tetra(1-cyclohepta-2,4,6-trienyl)phosphonium Tetrafluoroborate, [P(C₇H₇)₄]BF₄ The reaction of tris(trimethylsilyl)phosphane, P(SiMe₃)₃, with tropylium bromide, C₇H₇⁺Br^?, in polar solvents such as dichloromethane or tetrahydrofuran gives P(C₇H₇)₃ ( 1 ) and [P(C₇H₇)₄]Br ( 2a ). According to the X-ray crystallographic structure determinations, all 1-cyclohepta-2,4,6-trienyl substituents are present in the boat conformation in both P(C₇H₇)₃ ( 1 ) and the phosphonium salt, [P(C₇H₇)₄]BF₄ ( 2b ). The boat-shaped C₇H₇ rings are significantly more flattened if the phosphorus occupies the axial rather than the equatorial position at the ring substituent. Addition of a chalcogen to the lone pair at the central phosphorus atom of 1 leads to the chalcogena-phosphoranes EP(C₇H₇)₃ (E = O ( 3a ), S ( 3b ), Se ( 3c )). The new 1-cyclohepta-2,4,6-trienyl-phosphorus compounds 1, 2 b and 3a–c were characterized by their ¹H, ¹³C, and ³¹P NMR spectra in C₆D₆ solution.     

Coordinating properties of [M(CO)5(CN)] [M=Cr; Mo; W] ligands: formation of ion pairs or dinuclear cyanide-bridged complexes, spectroscopic and X-ray diffraction studies

The reaction of sodium cyanopentacarbonylmetalates Na[M(CO)₅(CN)] (M=Cr; Mo; W) with cationic Fe(II) complexes [Cp(CO)(L)Fe(thf)][O₃SCF₃], [L=PPh₃ (1a), CN-Benzyl (1b), CN-2,6-Me₂C₆H₃ (1c); CN-Bu^t (1d), P(OMe)₃ (1e), P(Me)₂Ph (1f)] in acetonitrile solution, yielded the metathesis products [Cp(CO)(L)Fe(NCCH₃)][NCM(CO)₅] [M=W, L=PPh₃ (2a), CN-Benzyl (2b), CN-2,6-Me₂C₆H₃ (2c); CN-Bu^t (2d), P(OMe)₃ (2e), P(Me)₂Ph (2f); M=Cr, L=(PPh₃) (3a), CN-2,6-Me₂C₆H₃ (3c); M=Mo, L=(PPh₃) (4a), CN-2,6-Me₂C₆H₃ (4c)]. The ionic nature of such complexes was suggested by conductivity measurements and their main structural features were determined by X-ray diffraction studies. Well-resolved signals relative to the [M(CO)₅(CN)] moieties could be distinguished only when ¹³C NMR experiments were performed at low temperature (from −30 to −50 °C), as in the case of [Cp(CO)(PPh₃)Fe(NCCH₃)][NCW(CO)₅] (2a) and [Cp(CO)(Benzyl-NC)Fe(NCCH₃)][NCW(CO)₅] (2b). When the same reaction was carried out in dichloromethane solution, neutral cyanide-bridged dinuclear complexes [Cp(CO)(L)FeNCM(CO)₅] [M=W, L=PPh₃ (5a), CN-Benzyl (5b); M=Cr, L=(PPh₃) (6a), CN-2,6-Me₂C₆H₃ (6c), CO (6g); M=Mo, L=CN-2,6-Me₂C₆H₃ (7c), CO (7g)] were obtained and characterized by infrared and NMR spectroscopy. In all cases, the room temperature ¹³C NMR measurements showed no broadening of cyano pentacarbonyl signals and, relative to tungsten complexes [Cp(CO)(PPh₃)FeNCW(CO)₅] (5a) and [Cp(CO)(CN-Benzyl)FeNCW(CO)₅] (5b), the presence of ¹⁸³W satellites of the ¹³CN resonances (J_CW ∼ 95 Hz) at room temperature confirmed the formation of stable neutral species. The main ¹³C NMR spectroscopic properties of the latter compounds were compared to those of the linkage isomers [Cp(CO)(PPh₃)FeCNW(CO)₅] (8a) and [Cp(CO)(CN-Benzyl)FeCNW(CO)₅] (8b). The characterization of the isomeric couples 5a-8a and 5b-8b was completed by the analyses of their main IR spectroscopic properties. The crystal structures determined for 2a, 5a, 8a and 8b allowed to investigate the geometrical and electronic differences between such complexes. Finally, the study was completed by extended Hückel calculations of the charge distribution among the relevant atoms for complexes 2a, 5a and 8a.