首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Halogeno-Nitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of [Na2(15-Crown-5)2(CH3CN)][MoCl4(NO)2] and [Na(15-Crown-5)]2[MoF4Cl(NO)] MoCl2(NO)2 and WCl2(NO)2, respectively, react with excess sodium fluoride in acetonitrile at room temperature and in the presence of 15-crown-5 to give crystalline mixtures, which consist of the title compounds, respectively of [Na(15-crown-5)]2[WCl4(NO)2] and [Na(15-crown-5)]2[WF4Cl(NO)], and which can be separated by selection. The complexes are characterized by their i.r. spectra, the molybdenum compounds additionally by crystal structure determinations. [Na2(15-crown-5)2(CH3CN)][MoCl4(NO)2]: Space group P21, Z = 2, 5415 independent unique reflexions, R = 0.039. Lattice dimensions at ?10°C: a = 984.3, b = 1231.1, c = 1483.0 pm, β = 105.67°. The compound consists of cations [Ne(l5-crown-5)(CH3CN)]+, in which the sodium ion is surrounded by the five O-atoms of the crown ether and by the N-atom of the acetonitrile molecule, as well as of anions, which form an ion pair {Na(15-crown-5)[MoCl4(NO)2]}?. In the in pairs the sodium ion is coordinated by the five oxygen atoms of the crown ether and by two chlorine atoms of the [MoCI4(NO)2]2? unit. The nitrosyl ligands take the cis-position a t the molybdenum atom which is in a distorted octahedrally fashion. [Na(15-crown-5)]2[MoF4Cl(NO)]. Space group C2/c, Z = 4, 1933 independent unique reflexions, R = 0.078. Lattice dimensions at ?7O°C: D : 1.585.8, b = 1171.5, c = 1771.5 pm, β = 114.91°. The compound forms an ion triple, in which the sodium ions are linked to five oxygen atoms each of the crown ether molecules, and to two F-atoms of the [MoF4Cl(NO)]2? unit. The F-atom which is arranged in trans-position to the nitrosyl ligand coordinates with both sodium ions; thus an unusual T-shaped arrangement results for this F-atom. The sole terminal F-Atom and the Cl-atom are disordered in two positions.  相似文献   

2.
Oxo-phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [Mo(O)2(NPPh3)2] and [WO(NPPh3)3]2[W6O19] The dioxo-phosphoraneiminato complexes [Mo(O)2(NPPh3)2] ( 1 ) and [W(O)2(NPPh3)2] ( 2 ) originate from hydrolysis of the nitrido complexes [MN(NPPh3)3] (M = Mo, W). They form colourless crystals, which are characterized by IR and NMR spectroscopy as well as by mass spectrometry. According to the crystal structure analysis of 1 (space group Fdd2, Z = 8; lattice dimensions at –83 °C: a = 1953.3(1), b = 3275.8(3), c = 953.4(1) pm) there are monomeric molecules with tetrahedrally coordinated molybdenum atoms. The distances MoO of 171.2 pm and MoN of 185.9 pm correspond to double bonds. In dichloromethane solution 2 undergoes further hydrolysis with colourless crystals of [WO(NPPh3)3]2[W6O19] ( 3 ) originating, which are characterized crystallographically (space group Pbcn, Z = 4; lattice dimensions at –50 °C: a = 3225.1(6), b = 1803.6(3), c = 1811.9(3) pm). 3 consists of cations [WO(NPPh3)3]+ with tetrahedrally coordinated tungsten atoms and of the known [W6O19]2– anions. The tungsten atoms of the cations show distances WO of 171.8 pm and WN of 182 pm which correspond to double bonds as in 1 .  相似文献   

3.
Stericly Shielded Nitrido Complexes of Molybdenum and Tungsten. The Crystal Structures of [MoN(NPh2)3] and [W4N4(NPh2)6(OnC4H9)2] The reactions of MoNCl3 and WNCl3, respectively, with lithium diphenylamide in tetrahydrofurane produce the monomeric nitrido complexes MN(NPh2)3 with CN = 4 at the metal atoms. In the presence of lithium-n-butyl LiNPh2 and WNCl3 also form the tetrameric nitrido complex [W4N4(NPh2)6(OnC4H9)2] which contains WV and WVI. The compounds are characterized by their i.r. spectra, by X-ray structural analysis, and, partially, by 1H and 13C n.m.r. spectroscopy. MoN(NPh2)3: Space group P1 , Z = 2, 4060 observed independent reflexions, R = 0.031. Lattice dimensions at 20°C: a = 956.2(4) pm, b = 1 015.9(2) pm, c = 1 598.1(3) pm; α = 79.06(2)°, β = 85.67(3)°, γ = 82.57(3)°. The compound forms monomeric molecules with Mo?N bond lengths of 163.4 pm and mean Mo? NPh2 distances of 199.2 pm. [W4N4(NPh2)6(OnC4H9)2]: Space group P21/n, Z = 2, 1903 observed independent reflexions, R=0.039. Lattice parameters at 19°C: a = 1582.2(3) pm, b = 1182.4(2) pm, c = 2053.3(4) pm; β = 103.77(2)°. The compound forms centrosymmetric molecules, in which the central W–W dumb-bell (bond length 253.5 pm) is linked by the nitrido ligands of two WN2(NPh2)2=units in a T shaped order of the N-atoms.  相似文献   

4.
Preparation and Vibrational Spectra of Dichloro and Dibromodithiophosphate. Crystal Structures of [PPh3Me][PS2Cl2] and [PPh4][PS2Br2] Dichloro and dibromodithiophosphates [Cat+][PS2X2?] with a large organic cation can be obtained from P4S10, CatX and HX in CH2Cl2 (Cat+ = PPh4+, PPh3Me+; X = Cl, Br). The vibrational spectra (i.r. and Raman) of the [PS2X2]? ions are reported and discussed; force constants were calculated. The crystal structures of [PPh3Me][PS2Cl2] and [PPh4][PS2Br2] were determined and refined with X-ray diffraction data. In both cases, simple anions [PS2X2]? are present. [PPh3Me][PS2Cl2]: orthorhombic, space group P212121, a = 1089, b = 1334, c = 1476 pm, Z = 4, refinement to a residual index R = 0.046 for 1116 reflexions; the structure is isotopic with [PPh3Me][VO2Cl2]. [PPh4][PS2Br2]: tetragonal space group I4 , a = 1301, c = 721 pm, Z = 2, refinement to R = 0.065 for 357 reflexions; the structure is isotypic with [AsPh4][FeCl4] with [PS2Br2]? ions occupying positions of 4 -symmetry with statistical orientation (statistical superposition of Br and S positions).  相似文献   

5.
Cyclothiazeno Complexes of Molybdenum(V), Molybdenum(VI), and Tungsten(VI). Crystal Structure of (PPh4)2[MoCl3(N3S2)]2 · 2 CH2Cl2 . From excess trithiazylchloride and molybdenum or tungsten hexacarbonyl, respectively, the cyclothiazeno complexes [MCl3(N3S2)]2(S2N2) are obtained. They possess metal atoms linked via a planar S2N2 ring. The corresponding bromo compounds [MBr3(N3S2)]2(S2N2) can be obtained in liquid bromine from S4N4 and MoBr4 or WBr6, respectively, or from S4N4 with the corresponding metal hexacarbonyls in the presence of bromine. Thermolysis of [WBr3(N3S2)]2(S2N2) yields [WBr3(N3S2)]2 which is dimerized via nitrogen bridges. When [MoCl3(N3S2)]2(S2N2) reacts with tetraphenylphosphonium chloride in dichloromethane, the S2N2 acts as reducing agent, and the paramagnetic molybdenum(V) complex (PPh4)2[MoCl3(N3S2)]2 · 2 CH2Cl2 is obtained (μeff = 1.2 B.M.). The i.r. spectra are reported. The crystal structure of (PPh4)2[MoCl3(N3S2)]2 · 2 CH2Cl2 was determined by X-ray diffraction (2524 independent reflexions, R = 0.052). It crystallizes in the space group P1 with the lattice con- stants a = 943.9, b = 1209.6, c = 1469.2 pm, α = 69.27, β = 72.20 and γ = 82.08°, Z = 1. There are tetraphenylphosphonium cations and centrosymmetric, dimeric anions [MoCl3(N3S2)]22?. The molybdenum atoms are part of six-membered cyclothiazeno rings MoN3S2 with MoN bond lengths of 177 and 197 pm; the N atom with the longer MoN bond is linked to the second Mo atom, so that a planar Mo2N2 ring results; this ring is nearly coplanar with the two MoN3S2 rings. Furthermore, each molybdenum atom is linked with three chlorine atoms with MoCl bond lengths of 240–242 pm, so that the Mo atoms possms a distorted octahedral coordination.  相似文献   

6.
New Phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [(μ‐S2N2){MoCl4(NPPh3)}2], [Mo(NPPh3)4][BF4]2, [W(S)2(NPPh3)2], and [Ph3PNH2]+[SCN] The binuclear molybdenum(V)phosphoraneiminato complex [(μ‐S2N2){MoVCl4(NPPh3)}2] ( 1 ) has been prepared by the reaction of the chlorothionitreno complex [MoVICl4(NSCl)]2 with Me3SiNPPh3 in dichloromethane forming green crystals. The temperature dependent magnetic susceptibility in the range of 2–30 K shows ideal behaviour according to the Curie law with a magnetic moment of 1.60 B.M. According to the crystal structure determination 1 forms centrosymmetric molecules in which the molybdenum atoms are connected by the nitrogen atoms of the S2N2 molecule. In trans‐position to it the nitrogen atoms of the phosphoraneiminato groups (NPPh3) are coordinated with Mo–N bond lengths of 171(1) pm. The tetrakis(phosphoraneiminato) complex [Mo(NPPh3)4]‐ [BF4]2 ( 2 ) has been obtained as colourless crystal needles by the reaction of MoN(NPPh3)3 with boron trifluoride etherate in toluene solution. In the dication the molybdenum atom is tetrahedrally coordinated by the nitrogen atoms of the (NPPh3) groups with Mo–N bond lengths of 179,8–181,0(3) pm. The dithio‐bis(phosphoraneiminato) tungsten complex [W(S)2(NPPh3)2] ( 3 ) is formed as yellow crystals as well as [Ph3PNH2]+[SCN] ( 4 ) from the reaction of WN(NPPh3)3 with carbon disulfide in tetrahydrofurane in the presence of traces of water. 3 has a monomeric molecular structure with tetrahedrally coordinated tungsten atom with bond lengths W–S of 214.5(5) pm and W–N of 179(1) pm. In the structure of 4 the thiocyanate ions are associated by hydrogen bonds of the NH2 group of the [Ph3PNH2]+ ion to give a zigzag chain. 1 : Space group Pbca, Z = 4, lattice constants at –80 °C: a = 1647.9(3), b = 1460.8(2), c = 1810.4(4) pm; R1 = 0.0981. 2 : Space group P1, Z = 2, lattice constants at –80 °C: a = 1162.5(1), b = 1238.0(1), c = 2346.2(2) pm; α = 103.14(1)°, β = 90.13(1)°, γ = 97.66(1)°; R1 = 0.0423. 3 : Space group Fdd2, Z = 8, lattice constants at –80 °C: a = 3310.1(4), b = 2059.7(2), c = 966,7(1) pm; R1 = 0.0696. 4 : Space group P212121, Z = 4, lattice constants at –80 °C: a = 1118.4(1), b = 1206.7(1), c = 1279.9(1) pm; R1 = 0.0311.  相似文献   

7.
Thiochlorowolframates with Tungsten(V) and (VI). Crystal Structures of PPh4[WSCl4] and (PPh4)2[WS2Cl4] · 2 CH2Cl2 Diamagnetic (NEt4)2[WSCl4]2, having tungsten atoms linked via sulfur atoms, is obtained by the reaction of WCl5 with NEt4SH as well as by the reduction of WSCl4 with NEt4I in dichloromethane. If the reduction is performed with PPh4I, PPh4[WSCl4] with monomer anions is formed. Reaction of WCl6 with H2S in dichloromethane yields brown, insoluble WS2Cl2 which has terminal W?S groups and bridging W? S? W groups according to its IR spectrum. WS2Cl2 and PPh4Cl react to afford PPh4[WS2Cl3] · 2 CH2Cl2 and (PPh4)2[WS2Cl4] · 2 CH2Cl2. IR spectra are reported. The crystal structures of PPh4[WSCl4] and (PPh4)2[WS2Cl4] · 2 CH2Cl2 were determined by X-ray diffraction. PPh4[WSCl4]: tetragonal, space group P4/n, Z = 2, a = 1292.3 pm, c = 763.2 pm; R = 0.054 for 898 observed reflexions. The [WSCl4]? ion has the structure of a square pyramid with a rather short W?S bond of 206 pm length. (PPh4)2[WS2Cl4] · 2 CH2Cl2: triclinic, space group P1 , a = 1017.7, b = 1114.5, c = 1243.4 pm, α = 70.61, β = 79.73, γ = 80.80°; R = 0.076 for 1804 reflexions. The [WS2Cl4]2? has cis configuration; as it is situated on an inversion center it shows positional disorder.  相似文献   

8.
Nitrosyl Complexes of Molybdenum (+II). Crystal Structures of [Mo(NO)Cl3 · POCl3]2 and [AsPh4]2[Mo(NO)Cl5] · 2 CH2Cl2 Solutions of MoCl5 in POCl3 react with NOCl forming the nitrosyl compound Mo(NO)Cl3 · 2POCl3 ( I ), which in CH2Cl2 cleaves off one solvate molecule, yielding the dimeric complex [Mo(NO)Cl3 · POCl3]2 ( II ). Reaction with AsPh4Cl in dichloro methane leads to the nitrosyl complexes AsPh4[Mo(NO)Cl4] · CH2Cl2 ( III ) and [AsPh4]2[Mo(NO)Cl5] · 2CH2Cl2 ( IV ), respectively. The i.r. spectra are recorded and assigned. [Mo(NO)Cl3 · POCl3]2 crystallizes monoclinic in the space group P21/c with two dimeric units per unit cell. The crystal structure was determined by X-ray diffraction methods (R = 0.040; 1391 observed, independent reflexions). Complex II is linked by chlorine bridges, forming a dimeric, centrosymmetric molecule of symmetry Ci. The N? O bond of the nitrosyl ligand is extremely short (108 pm), the Mo? N bond (181 pm) corresponds to a double bond. In trans position to the NO ligand, which is coordinated in linear array, there is the O atom of the solvate molecule POCl3. [AsPh4]2[Mo(NO)Cl5] · 2 CH2Cl2 crystallizes triclinic in the space group P1 with two units per unit cell (R = 0.039; 1967 observed, independent reflexions). The molybdenum atom is coordinated octahedrally by five Cl ligands and a nitrosyl group, as well coordinated in linear array (Mo? N? O 174°). The nitrosyl ligand exerts a significant trans-effect (r Mo? Cl(trans) = 247 pm, r MoCl4(eq)(average) = 239 pm).  相似文献   

9.
Disulfido-Bridged Halo Complexes of Molybdenum (V). Crystal Sructures of (PPh3Me)2 [Cl4Mo (μ-S2)2MoCl4]. 2 CH2Cl2 and (PPh4)2[Br4Mo(μ-S2)2MoBr4]. 3CH2Br2 . Mo(S2)Cl3 is prepared by an improved method; the i.r. spectrum is reported. In dichloro methane solution it reacts with (PPh3Me)Cl forming the complex (PPh3Me)2[Cl4Mo(μ-S2)2MoCl4] · 2 CH2Cl2. The bromo complex (PPh4)2[Br4Mo(μ-S2)2MoBr4] · 3 CH2Br2 is obtained by reaction of MoBr4 with S7NH and subsequent treatment of the reaction mixture with PPh4Br in CH2Br2 solution. Both complexes are characterized by i.r. spectra and structural analyses by X-ray methods. (PPh3Me)2[Cl4Mo(μ-S2)2MoCl4] · 2 CH2Cl2 crystallizes monoclinic in the space group P21/c with two formula units per unit cell (5268 observed independent reflexions, R = 4.0%). The lattice dimensions are: a = 1097 pm, b = 1510 pm, c = 1591 pm, β = 104.4°. (PPh4)2[Br4Mo(μ-S2)2MoBr4] · 3 CH2Br2 crystallizes triclinic in the space group P&1macr; with two formula units per unit cell and the lattice constants a = 1328 pm, b = 1573 pm, c = 1719 pm, α = 95.8°, β = 96.3°, γ = 74.1°. Both compounds are of ionical structure with PPh3Me and PPh4 cations, respectively, and anions [X4MO(μ-S2)2MoX4]2? very similar to each other. The molybdenum atoms are bridged by two disulfido ligands and are bonded directly with a bond length of 286 pm. The terminal halogen atoms add up to coordination number nine at the molybdenum.  相似文献   

10.
The temperature dependence of the thermal decay of α-MoCl3 was determined and the entropies of MoCl3 and MoCl2 calculated. The decomposition behaviour of MoOCl2 under equilibrium conditions may be described by the equation The decomposition reactions 6 MoOCl2,s = Mo + MoO2 + 4 MoOCl3,g has only inferior importance. From the results the enthalpy and entropy values of MoOCl2 are derived (data see “Inhaltsübersicht”).  相似文献   

11.
Crystal Structures of the Hexachlorometalates NH4[SbCl6], NH4[WCl6], [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 and (PPh4)2[WCl6]·4CH3CN The crystal structures of the title compounds were determined by single crystal X‐ray methods. NH4[SbCl6] and NH4[WCl6] crystallize isotypically in the space group C2/c with four formula units per unit cell. The NH4+ ions occupy a twofold crystallographic axis, whereas the metal atoms of the [MCl6] ions occupy a centre of inversion. There exist weak interionic hydrogen bridges. [K(18‐crown‐6)(CH2Cl2)]2[WCl6]·6CH2Cl2 crystallizes in the orthorhombic space group R3¯/m with Z = 3. The compound forms centrosymmetric ion triples, in which the potassium ions are coordinated with a WCl3 face each. In trans‐position to it the chlorine atom of a CH2Cl2 molecule is coordinated so that, together with the oxygen atoms of the crown ether, coordination number 10 is achieved. (PPh4)2[WCl6]·4CH3CN crystallizes in the monoclinic space group P21/c with Z = 4. This compound, too, forms centrosymmetric ion triples, in which in addition the acetonitrile molecules are connected with the [WCl6]2— ion via weak C—H···Cl contacts.  相似文献   

12.
Reactions of Dimethyl Sulfoxide with Molybdenum Tetrabromide and Molybdenum Dibromide Dinitrosyl. Crystal Structure of [MoBr2(NO)2(OSMe2)2] In the cold molybdenum tetrabromide reacts with an equivalent amount of dimethyl sulfoxide forming the solvate [MoBr4(OSMe2)2]; excess dimethyl sulfoxide yields [MoO2Br2(OSMe2)2] which is also obtained by other methods. Molybdenum dibromidedinitrosyl forms the solvate [MoBr2(NO)2(OSMe2)2] in the reaction with dimethyl sulfoxide. According to the i.r. spectra all complexes display O-coordination of the OSMe2 molecules. [MoBr2(NO)2(OSMe2)2] crystallizes monoclinic in the space group P21/c with four formula units per unit cell. The cell dimensions are a = 1236, b = 892, c = 1305 pm, β = 95.2°. 1662 independent observed reflexions were used for refinement; R = 3.8%. The molybdenum atoms are six-coordinated, the O atoms of the dimethyl sulfoxide molecules are in trans-position to the nitrosyl ligands, which form linear groups Mo? N? O.  相似文献   

13.
Reactions of Uranium Pentabromide. Crystal Structures of PPh4[UBr6], PPh4[UBr6] · 2CCl4, (PPh4)2[UBr6] · 4CH3CN, and (PPh4)2[UO2Br4] · 2CH2Cl2 PPh4[UBr6] and PPh4[UBr6] · 2CCl4 were obtained from UBr5 · CH3CN and tetraphenylphosphonium bromide in dichloromethane, the latter being precipitated by CCl4. Their crystal structures were determined by X-ray diffraction. PPh4[UBr6]: 2101 observed reflexions, R = 0.090, space group C2/c, Z = 4, a = 2315.5, b = 695.0, c = 1805.2 pm, β = 96.38°. PPh4[UBr6] · 2CCl4: 2973 reflexions, R = 0.074, space group P21/c, Z = 4, a = 1111.5, b = 2114.2, c = 1718.7 pm, β = 95.42°. Hydrogen sulfide reduces uranium pentabromide to uranium tetrabromide. Upon evaporation, bromide is evolved from solutions of UBr5 with 1 or more then 3 mol equivalents of acetonitrile in dichlormethane yielding UBr4 · CH3CN and UBr4 · 3CH3CN, respectively. These react with PPh4Br in acetonitrile affording (PPh4)2[UBr6] · 4CH3CN, the crystal structure of which was determined: 2663 reflexions, R = 0.050, space group P21/c, Z = 2, a = 981.8, b = 2010.1, c = 1549.3 pm, β = 98.79°. By reduction of uranium pentabromide with tetraethylammonium hydrogen sulfide in dichloromethane (NEt4)2[U2Br10] was obtained; (PPh4)2[U2Br10] formed from UBr4 and PPh4Br in CH2Cl2. Both compounds are extremely sensitive towards moisture and oxygen. The crystal structure of the oxydation product of the latter compound, (PPh4)2[U02Br4]· 2 CH2Cl2, was determined: 2163 reflexions, R = 0.083, space group C2/c, Z = 4, a = 2006.3, b = 1320.6, c = 2042,5 pm, β = 98.78°. Mean values for the UBr bond lengths in the octahedral anions are 266.2 pm for UBr6-, 276.7 pm for UBr62? and 282.5 pm for UO2Br42?  相似文献   

14.
Reaction of Tin Chlorides with Polysulfides. Crystal Structures of (PPh4)2[SnCl2(S6)2], (PPh4)2[Sn4Cl4S5(S3)O], and (PPh4)2[SnCl6] · S8 · 2CH3CN . The reaction of PPh4[SnCl3] with Na2S4 in acetonitrile in the presence of small amounts of water yields (PPh4)2[Sn4Cl4S5(S3)O] and minor amounts of (PPh4)2[SnCl2(S6)2], PPh4Cl · 2S8 and (PPh4)2[SnCl6]. SnCl4 is partially reduced by (PPh4)2Sx, PPh4[SnCl3] and (PPh4)2[SnCl6] · S8 · 2CH3CN being produced. According to the X-ray crystal structure determination the [Sn4Cl4S5(S3)O]2?-ion consists of an O atom that is coordinated by four Sn atoms which in turn are liked with one another by five single S atoms and one S3 group. In the [SnCl2(S6)2]2?-ion the Sn atom is octahedrally coordinated by two Cl atoms in trans arrangement and by two chelating S6 groups. Octahedral [SnCl6]2? ions and S8 molecules in the crown conformation are present in (PPh4)4[SnCl6] · S8 · 2CH3CN.  相似文献   

15.
Thiocomplexes of Molybdenum. Crystal Structure of a Mixed Single Crystal (PPh3Me)2[Mo2Br6(NO)4]/(PPh3Me)2[Mo2Br6S2(NO)2] The reactions of (PPh4)2MoS4 with MoBr4 and MoBr2(NO)2 resp. lead to the binuclear complexes (PPh4)2[S2MoS2MoBr3(SMe2)] and (PPh4)[S2MoS2MoBr2(NO)2], in which the molybdenum atoms are linked by sulfido bridges. The preparation of (PPh3Me)2S6 and (AsPh4)2S7 from Na2S4 and PPh3MeBr, and AsPh4Cl, respectively, in ethanol solution is described. Disulfido briges are a feature of (AsPh4)2[Mo2Br6(S2)2(SMe2)2], which is obtained from MoBr4(SMe2)2 and (AsPh4)2S7. Mixed single crystals containing 2/3 (PPh3Me)2[Mo2Br6(NO)4] and 1/3 (PPh3Me)2[Mo2Br6S2(NO)2] are formed in the reaction of MoBr2(NO)2 with (PPh3Me)2S6, as shown by X-ray single crystal structure determination. The compound crystallizes monoclinic in the space group C2/c (Internat. Tab. Nr. 15) with four formula units per unit cell (2351 independent observed reflexions, Rw = 0.037). The cell parameters are a = 1603 pm, b = 1549 pm, c = 1863 pm; β = 92.2°. The complexes consist of PPh3Me cations and the dimeric anions [Mo2Br6(NO)4]2? and [Mo2Br6S2(NO)2]2? which occur in the ratio 2:1. In these the molybdenum atoms are connected via MoBr2Mo bridges of slightly different lengths (Mo? Br 265 pm and 267 pm) forming a controsymmetric double octahedron. All molybdenum atoms have two terminal bromo ligands with Mo? Br bond lengths of 258 pm and 260 pm; in the [Mo2Br6(NO)4]2? ion each molybdenum has two covalently bonded nitrosyl groups on cis-position with Mo? N bond lengths of 183 pm. In the [Mo2Br6S2(NO)2]2? ion one of the two nitrosyl groups at each metal atom is substituted by a terminal sulfido ligand with a Mo? S bond length of 240 pm. The i.r. spectra are reported.  相似文献   

16.
Azido Complexes of Manganese(II) and Cobalt(II). Crystal Structures of (PPh4)2[Mn(N3)4] and PPh42[Co(N3)3Cl] (PPh4)2[Mn(N3)4] and (PPh4)2[Co(N3)3Cl] were obtained as light-brown and green blue, nonexplosive crystalline compounds, respectively. They are only slightly sensitive to moisture and were obtained from the tetrachloro complexes (PPh4)2MCl4 by reactions with silver azide in dichloromethane. The compounds were characterized by thier i.r. spectra and by crystal structure analyses. Both crystallized in the monoclinic space group C2/c, Z = 4, but they are not isotypic. (PPh4)2[Mn(N3)4]: structure determination with 711 independent reflexions, R = 0.097; a = 2249.1, b = 1499.6, c = 1370.3 pm, β = 104.86°. (PPh4)2[Co(N3)Cl]: 2753 reflexions, R = 0.075; a = 1119.7, b = 1899.2, c = 2115.4 pm, β = 90.47°. The structures consist of PPh4+ ions and of anions that are situated on twofold crystallographic rotation axes. The anions show positional disorder, statistically assuming two different orientations with probabilities of 50% each; in the case of [Co(N3)3Cl]2?, the Cl atom is superimposed statistically with an azido group, whereas the [Mn(N3)4]2? ion is tilted by about 20° from the ideal position to two sides of the crystallographic axis. In both compounds the cation form layers and the anions are located between the layers.  相似文献   

17.
Bromo Complexes of Molybdenum(IV) [MoBr6]2? and [Mo2Br10]2?. Crystal Structure of (PPh3Me)2[MoBr6] · 2 CH2Br2 The bromomolybdates(IV) (PPh3Me)2[MoBr6] · 2 CH2Br2 and (PPh4)2[Mo2Br10] are obtained by reactions of molybdenum tetrabromide with PPh3MeBr and PPh4Br, respectively. They form black-brown, hydrolysis sensitive crystal powders. The crystal structure of (PPh3Me)2[MoBr6] · 2 CH2Br2 was determined by X-ray diffraction (2376 independent observed reflexions, R = 0.082). Crystal data: a = 1024, b = 1131, c = 1179 pm, α = 108.2°, β = 106.8°, γ = 99.0°, space group P1 , Z = 1. The compound consists of PPh3Me+ ions, CH2Br2 molecules and nearly octahedral [MoBr6]2? ions with MoBr bond lengths between 252.7 and 254.0 pm.  相似文献   

18.
Cyclo-S2N2 Bridged Chlorothionitrene Complexes of Molybdenum and Tungsten. Crystal Structure of μ-(S2N2)[MoCl4(NSCl)]2 Molybdenum pentachloride reacts with (NSCl)3 in CH2Cl2 suspension giving a product mixture from which the complex μ-(S2N2)[MoCl4(NSCl)]2 can be extracted with CH2Cl2. It forms black crystals, whereas the corresponding tungsten compound forms copper-red crystals. μ-(S2N2)[WCl4(NSCl)]2 is obtained by abstraction of SCl2 and chlorine from N(SCl)2[WCl5(NSCl)], which can be obtained from WCl6 and N2S3Cl2. According to their i.r. spectra both complexes μ-(S2N2)[MCl4(NSCl)]2 have the same molecular structure. The crystal structure of μ-(S2N2)[MoCl4(NSCl)]2 was determined and refined with X-ray diffraction data (1851 reflexions, R = 0.019). It crystallizes in the triclinic space group P1 with two molecules per unit cell. The lattice constants are a = 685, b = 735, c = 963 pm, α = 76.6°, β = 80.9°, γ = 87.0°. μ-(S2N2)[MoCl4(NSCl)]2 forms centrosymmetric molecules in which the Mo atoms of the MoCl4(NSCl) units are linked via the N atoms of a planar N2S2 ring. The Mo atoms have coordination number 6, having the N atom of the chlorothionitrene ligand Mo in trans position to the N atom of the S2N2 ring.  相似文献   

19.
Synthesis and Crystal Structures of (PPh4)2[TeS3] · 2 CH3CN and (PPh4)2[Te(S5)2] (PPh4)2[TeS3] · 2 CH3CN was obtained by the reaction of PPh4Cl, Na2S4 and Te in acetonitrile. With sulfur it reacts yielding (PPh4)2[Te(S5)2]. The crystal structures of both products were determined by X-ray diffraction. (PPh4)2[TeS3] · 2 CH3CN: triclinic, space group P1 , Z = 2, R = 0.041 for 4 629 reflexions; it contains trigonal-pyramidal [TeS3]2? ions with an average Te? S bond length of 233 pm. (PPh3)2[Te(S5)2]: monoclinic, P21/n, Z = 2, R = 0.037 for 2 341 reflexions. In the [Te(S5)2]2? ion the tellurium atom has a nearly square coordination by four S atoms. Along with the Te atoms each of the two S5 groups forms a ring with chair conformation.  相似文献   

20.
Dichlorophosphate Complexes of the Nitrido Chlorides of Molybdenum and Tungsten Tetraphenylarsonium dichlorophosphate AsPh4[PO2Cl2], is prepared by the reaction of AsPh4Cl with P2O3Cl4. The vibrational spectrum is reported as well as the valence force constants of the [PO2Cl2]? ion. The f-values are clearly smaller than those of the isoelectronic SO2Cl2 molecule. The dichlorophosphate ion forms complexes with the nitride chlorides MNCl3 (M ? Mo, W) of the type [MNCl3(PO2Cl2)]22?, which are characterized by their i.r. spectra.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号