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1.
The Crystal Structure of Tetraphenylarsonium-tetrabromooxotechnetate(V), (Ph4As)TcOBr4 (Ph4As)TcOBr4 has been prepared from (Bu4N)TcO4, HBr and (Ph4As)Br. The crystal structure of the complex has been determined by X-ray diffraction using MoKα radiation. The crystals are tetragonal, space group P 4/n with a = 1276.6(1) pm, c = 803.2(1) pm, Z = 2. The refinement based on 1595 reflexes converged to R = 0.034. The structure consists of discrete TcOBr4? anions and Ph4As+ cations. The technetium is coordinated in a square pyramidal environment. A C4v symmetry was derived for the complex anion. With this, it is isomorphous to the other structurally studied (Ph4As)TcYX4 complexes (Y = O, N; X = Cl, Br). The Tc = O length is 161.3(9) pm with Tc? Br 246.0(1) pm  相似文献   

2.
Radical-ion salts bis(biphenyl)chromium(i) 1,4-di(2-cyanoisopropyl)-1,4-dihydrofulleride [(Ph2)2Cr][1,4-(CMe2CN)2C60]−· and bis(biphenyl)chromium(i) 1-(2-cyanoisopropyl)-1,2-dihydrofulleride [(Ph2)2Cr][1,2-(CMe2CN)(H)C60]−·, the salt bis(biphenyl)chromium(i) (2-cyanoisopropyl)fulleride [(Ph2)2Cr][(CMe2CN)C60], and neutral 1-(2-cyanoisopropyl)-1,2-dihydrofullerene 1,2-(CMe2CN)(H)C60 have been synthesized for the first time. The compounds [(Ph2)2Cr][1,4-(CMe2CN)2C60]−· and [(Ph2)2Cr][1,2-(CMe2CN)(H)C60]−· decompose in THF to form [(Ph2)2Cr][(CMe2CN)C60], whose protonation affords 1,2-(CMe2CN)(H)C60. 1,4-Di(2-cyanoisopropyl)-1,4-dihydrofullerene 1,4-(CMe2CN)2C60 and 1,2-(CMe2CN)(H)C60 are stable in vacuo up to 513 K. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1935–1939, September, 2008.  相似文献   

3.
Benzyl-tris(trimethylsilyl)methyl Tin Dihalides, {(CH3)3Si}3C(C6H5–CH2)SnHal2 with Hal = Cl, Br, I The tin tetrahalides SnHal4 (Hal = Cl, Br, I) react with base-free tris(trimethylsilyl)methyllithium (Tsi–Li) solved in toluene to form the trihalides Tsi–SnHal3. But when the reaction is carried out in a 1 : 2 molar ratio at 60 °C in toluene, Tsi–H, Tsi–Hal and benzyl-trisyl tin-dihalides are formed in good yields, respectively. The nmr (1H, 13C, 29Si, 119Sn) and the Raman spectra are discussed, the X-ray structure analyses of the dibromide as well as the diiodide have been measured.  相似文献   

4.
Structural Chemistry of the Alkyl- and Arylhaloarsenates(III) [Me2As2Cl5], [RAsCl3], [R2As2Br6]2– (R = Me, Et, Ph) and [Ph2AsX2] (X = Cl, Br) The alkyl- and arylhaloarsenates(III) [Ph4P][Me2As2Cl5] ( 1 ), [Ph4P][RAsCl3] (R = Me, Et, Ph, 2 – 4 ), [Me3PhN][PhAsCl3] ( 5 ), [Ph4P]2[R2As2Br6] (R = Me, Et, Ph, 6 – 8 ), [n-Pr4N][Ph2AsCl2] ( 9 ) and [n-Bu4N][Ph2AsBr2] ( 10 ) have been prepared and their structures established by X-ray diffraction. In contrast to the chloroarsenates(III) 2 – 5 , which all contain isolated ψ-trigonal bipyramidal anions [RAsCl3], the analogous bromoarsenates(III) 6 – 8 exhibit dimeric structures. Whereas the trans sited As–Cl distances in 2 and 3 are very similar a pronounced degree of asymmetry is apparent for the Cl–As–Cl three-centre bonds in 4 and 5 [2.396(1) and 2.602(1) Å in 5]. In 6 and 7 Ci symmetry related RAsBr2 units are connected through long As…Br bonds [2.926(1) and 3.116(2) Å in 6 ]. The bromophenylarsenate(III) anion of 8 which contains two effectively undistorted ψ-trigonal bipyramids [PhAsBr3] associated by weak As…Br interactions [3.117(2) Å]. In view of its very long bridging As…Cl distances the [Me2As2Cl5] anion in 1 can, as 6 an 7 , be regarded as two MeAsCl2 molecules weakly linked through a chloride ion.  相似文献   

5.
Electrocrystallization of Fullerides The fullerides P(C6H5)4C60 · P(C6H5)4Cl, P(C6H5)4C60 · P(C6H5)4Br und As(C6H5)4C60 · As(C6H5)4Cl have been prepared by electrocrystallization. Single crystal structure determinations have shown them to be isostructural in space group I4/m with lattice constants a = 12.5731(9), c = 20.142(3) Å; a = 12.5378(10), c = 20.606(5) Å; a = 12.6003(11), c = 20.377(4) Å, respectively. Spectroscopic and magnetic investigations prove the existence of a C60? anion, showing orientational disorder in all three fullerides.  相似文献   

6.
The reaction of Ph2P(S)N(SiMe3)2 with potassium tert-butoxide in a 1:1 molar ratio produces K[Ph2P(S)NSiMe3], which was converted to the AsPh4+ salt by metathesis with [AsPh4]Cl. The X-ray crystal structure of [AsPh4][Ph2P(S)NSiMe3] · 0.5 THF consists of noninteracting AsPh4+ and Ph2P(S)NSiMe3? ions with d(P? S) = 1.980(4) Å and d(P? N) = 1.555(8) Å. The PNSi bite angle in the anion is 136.3(5)°. Electrophilic attack by Ph2P(S)Cl occurs at the sulfur atom of Ph2P(S)NSiMe3?. The oxidation of the anion with iodine produces a disulfide which regenerates K[Ph2P(S)NSiMe2] upon treatment with potassium tert-butoxide.  相似文献   

7.
Syntheses and Crystal Structures of [(Ph3As)2CCN–MnBr3], [(Ph3As)2CCN–CoBr3], and [(Ph3As)2CCN]+CuBr2 The di(arsa)acetonitrilium bromide [(Ph3As)2CCN]Br reacts with the anhydrous dibromides of manganese and cobalt in acetonitrile to form the molecular complexes [(Ph3As)2CCN–MBr3] [M = ( 1 ), Co( 2 )] with zwitterionic structures. With copper(I)bromide, however, the ionic compound [(Ph3As)2CCN]+CuBr2 ( 3 ) is formed. All complexes are characterized by IR spectroscopy and by crystal structure analyses. 1 and 2 crystallize isotypically with each other in the space group P 1 with two formula units per unit cell. The MBr3 fragments in the molecular complexes are connected to the N atom of the [(Ph3As)2CCN]+ cation showing bond angles C–N–Mn of 156.9° and C–N–Co of 161°, and distances Mn–N of 215.6 pm and Co–N of 201 pm. In 3 , on the other hand, (space group C2/c, Z = 4) the ions [(Ph3As)2CCN]+ and the linear Br–Cu–Br ion are to be found concurrent but separate.  相似文献   

8.
Reaction of Mo(CO)(η2‐C2Ph2)24‐C4Ph4) and Me3NO in acetonitrile solvent affords Mo(NCMe)(η2‐C2Ph2)24‐C4Ph4) 1 . Compound 1 reacts with trimethylphosphine to produce Mo(PMe3)(η2‐C2Ph2)24‐C4Ph4) 2 , or reacts with diphenylacetylene to produce (η5‐C5Ph5)2Mo 3 and Mo(η2‐O2CPh)(η4‐C4Ph4H)(η4‐C4Ph4) 4 . The molecular structures of 1, 2 and 4 have been determined by an X‐ray diffraction study.  相似文献   

9.
The Preparation of Methylthio(trihalogeno)phosphonium Salts ClnBr3?nPSCH3+MF6?(n = 0–3; M = As, Sb) and Hal3PSCH3+SbCl6?(Hal = Br, Cl) The methylthio(trihalogeno) phosphonium salts BrnCl3?nPSCH3+MF6? (n = 0–3; M = As, Sb) are prepared by methylation of the corresponding thiophosphorylhalides BrnCl3?nPS in the system SO2/CH3F/MF5. The hexachloroantimonates Hal3PSCH3+SbCl6?(Hal = Br, Cl) are synthesized by thiomethylation of PBr3 and PCl3 with CH3SCl/SbCl5. All salts are characterized by vibrational and NMR spectroscopy.  相似文献   

10.
Chloro- and Polyselenoselenates(II): Synthesis, Structure, and Properties of [Ph3(C2H4OH)P]2[SeCl4] · MeCN, [Ph4P]2[Se2Cl6], and [Ph4P]2[Se(Se5)2] By symproportionation of elemental selenium and SeCl4 in polar protic solvents the novel chloroselenates(+II), [SeCl4]2? and [Se2Cl6]2?, could be stabilized; they were crystallized with voluminous organic cations. They were characterized from complete X-ray structure analysis. Yellow-orange [Ph3(C2H4OH)P]2[SeCl4] · MeCN (space group P1 , a = 10.535(4), b = 12.204(5), c = 16.845(6) Å, α = 77.09(3)°, β = 76.40(3)°, γ = 82.75(3)° at 140 K) contains in its crystal structure monomeric [SeCl4]2? anions with square-planar coordination of Se(+II). The mean Se? Cl bond length is 2.441 Å. In yellow [Ph4P]2[Se2Cl6] (space group P1 , a = 10.269(3), b = 10.836(4), c = 10.872(3) Å, α = 80.26(3)°, β = 79.84(2)°, γ = 72.21(3)° at 140 K) a dinuclear centrosymmetric [Se2Cl6]2? anion, also with square-planar coordinated Se(+II), is observed. The average terminal and bridging Se? Cl bond distances are 2.273 and 2.680 Å, respectively. From redox reactions of elemental Se with boranate/thiolate in ethanol/DMF the bis(pentaselenido)selenate(+II) anion [Se(Se5)2]2? was prepared as a novel type of a mixed-valent chalcogenide. In dark-red-brown [Ph4P]2[Se(Se5)2] (space group P21/n, a = 12.748(4), b = 14.659(5), c = 14.036(5) Å, β = 108.53(3)° at 140 K) centrosymmetric molecular [Se(Se5)2]2? anions with square-planar coordination of the central Se(+II) by two bidentate pentaselenide ligands is observed (mean Se? Se bond lengths: 2.658 Å at Se(+II), 2.322 Å in [Se5]2?). The resulting six-membered chelate rings with chair conformation are spirocyclically linked through the central Se(+II). The vibrational spectra of the new anions are reported.  相似文献   

11.
Efficiencies and rates of electron transfer from various electron donors to excited fullerenes (C60 and C70) have been determined by observing the transient absorption bands in the near-IR region, where the anion radicals of fullerenes appear. From the rise of the absorption bands of C60 −+ and C70 −+ in the near-IR region, electron transfer takes place via the triplet states (TC60 * and TC70 *) under appropriately low concentrations of electron donors. By analysis of the rise curves C60 −+ and C70 −+, contribution of the excited singlet states (SC60 * and SC70 *) in addition to the route of the triplet states (TC60 * and TC70 *) is confirmed. The quantum yield for electron transfer via the triplet states Φct T was evaluated by the ratio of [C60 −+]/[TC60 *] (or [C70 −+/[TC70 *]). The Φct T depends upon the donor-ability, donor concentration, and solvent polarity. The back electron-transfer process, which was evaluated by observing C60 −+, also depends upon the solvent polarity.  相似文献   

12.
Crystal Structure Determinations of Bis(pentafluorophenyl)tellurium Dihalides (C6F5)2TeHal2 (Hal = Cl, Br) Bis(pentafluorophenyl)telluriumdichloride and bis(pentafluorophenyl)telluriumdibromide crystallize at 10°C or 20°C from CH2Cl2 or CHCl3 solution in the monoclinic space group P21/c with a = 649.5(1) pm, b = 1 275.6(2) pm, c = 1 816.2(5) pm, β = 92.89(2)° for (C6F5)2TeCl2 and a = 694.4(1) pm, b = 1 579.1(2) pm, c = 1 423.4(1) pm, β = 90.22(2)° for (C6F5)2TeBr2 with four formula units per each unit cell.  相似文献   

13.
The interaction of the ytterbium bis(indenyl) complex (C9H7)2YbII(THF)2 (1) with the 1,4-diazabutadiene 2-MeC6H4N=C(Me)-C(Me)=NC6H4Me-2 (MeDAD) is accompanied by the oxidation of the metal atom to the trivalent state and results in a paramagnetic compound of the metallocene type (C9H7)2YbIII(MeDAD−·) (3) containing the radical anion of 1,4-diazabutadiene. The structure of the complex 3 was determined by X-ray diffraction analysis. The reactions of the bis(indenyl) (1) and bis(fluorenyl) (C13H9)2YbII(THF)2 (2) derivatives of divalent ytterbium with the 1,4-diazabutadiene PhN=C(Ph)-C(Ph)=NPh (PhDAD) (with the molar ratio of the reactants 1:2) proceed with a complete cleavage of the bonds Yb-C and the oxidation of the ytterbium atom to the trivalent state and result in a homoligand complex (PhDAD−·)3Yb (6) containing three radical anion 1,4-diazadiene ligands. Complex 6 was also obtained by an exchange reaction of YbCl3 with PhDAD−·K+ (1: 3) in THF. Complex 6 was characterized by X-ray diffraction analysis.  相似文献   

14.
The Reaction of Ph3AsCl2 with Acetonitrile. Crystal Structures of [Ph3AsNC(Me)C(AsPh3)CN]+Cl and of the Palladium Molecular Complex [Ph3AsNC(Me)C(AsPh3)CN–PdCl3] In the presence of potassium hydride the reaction of Ph3AsCl2 with acetonitrile leads to [Ph3AsNC(Me) · C(AsPh3)CN]+Cl ( 1 ), which is characterized by its infrared spectrum and by a crystal structure analysis. 1 can be explained as an insertion reaction of acetonitrile into an ylidic As–C bond of the primarily formed [(Ph3As)2CCN]Cl. 1 : Space group P1, Z = 2, lattice dimensions at –70 °C: a = 991.9(1), b = 1255.2(1), c = 1381.3(1) pm, α = 81.64(1)°, β = 80.12(1)°, γ = 78.17(1)°; R1 = 0.051. 1 reacts with palladium(II) chloride to give the molecular complex [Ph3AsNC(Me)C(AsPh3)CN–PdCl3] ( 2 ) with zwitterionic structure. The fragment {PdCl3} is terminally bonded at the nitrogen atom of the CCN group of the cation of 1 in a linear arrangement CCNPd. 2 · CH3CN: Space group P21, Z = 2, lattice dimensions at –90 °C: a = 1079.2(1), b = 1261.5(1), c = 1560.9(1) pm; β = 110.20(1)°; R1 = 0.0283.  相似文献   

15.
Chemical ionization (CI) mass spectra of C60-fullerene were studied using 1,2-dibromoethane and 1,2-dichloroethane as CI reagents. The ion-molecule reaction between C60 and C2H4X+ (X=Br and Cl) leads to the formation of (C60+C2H4X)+ adducts. The collision-induced dissociation of the adducts reveal gas phase halo alkylation of C60-fullerence involving the C?C bond formation.  相似文献   

16.
Summary.  The reaction of elemental antimony with elemental sulfur and [Ph4P]Br in an aqueous solution of neopentanediamine under solvothermal conditions yields yellow needles of the new thioantimonate(III) [Ph4P]2[Sb6S10]. The structure consists of [Ph4P]+ cations and infinite one-dimensional anionic (Sb6S10 2−)n chains running along the crystallographic a axis. The chains are composed of 10-membered Sb5S5 rings with alternating Sb and S atoms and separated by the tetraphenylphosphonium cations. Upon heating the compound decomposes in two distinct steps, starting at about 100°C. The final product was identified by X-ray powder diffractometry as Sb2S3. Received December 17, 1999. Accepted (revised) February 7, 2000  相似文献   

17.
The haloacyltris(trifluoromethyl)borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been synthesized by reacting (CF3)3BCO with either MHal (M=K, Cs; Hal=F) in SO2 or MHal (M=[nBu4N]+, [Et4N]+, [Ph4P]+; Hal=Cl, Br, I) in dichloromethane. Metathesis reactions of the fluoroacyl complex with Me3SiHal (Hal=Cl, Br, I) led to the formation of its higher homologues. The thermal stabilities of the haloacyltris(trifluoromethyl)borates decrease from the fluorine to the iodine derivative. The chemical reactivities decrease in the same order as demonstrated by a series of selected reactions. The new [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br) salts are used as starting materials in the syntheses of novel compounds that contain the (CF3)3B-C fragment. All borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been characterized by multinuclear NMR spectroscopy (11B, 13C, 17O, 19F) and vibrational spectroscopy. [PPh4][(CF3)3BC(O)Br] crystallizes in the monoclinic space group P2/c (no. 13) and the bond parameters are compared with those of (CF3)3BCO and K[(CF3)3BC(O)F]. The interpretation of the spectroscopic and structural data are supported by DFT calculations [B3LYP/6-311+G(d)].  相似文献   

18.
The reaction of Ru3(CO)10(dotpm) ( 1 ) [dotpm = (bis(di‐ortho‐tolylphosphanyl)methane)] and one equivalent of L [L = PPh3, P(C6H4Cl‐p)3 and PPh2(C6H4Br‐p)] in refluxing n‐hexane afforded a series of derivatives [Ru3(CO)9(dotpm)L] ( 2 – 4 ), respectively, in ca. 67–70 % yield. Complexes 2 – 4 were characterized by elemental analysis (CHN), IR, 1H NMR, 13C{1H} NMR and 31P{1H} NMR spectroscopy. The molecular structures of 2 , 3 , and 4 were established by single‐crystal X‐ray diffraction. The bidentate dotpm and monodentate phosphine ligands occupy equatorial positions with respect to the Ru triangle. The effect of substitution resulted in significant differences in the Ru–Ru and Ru–P bond lengths.  相似文献   

19.
Metal Complexes of Biologically Important Ligands. CXVII [1] Addition of the O'Donnell Reagent [Ph2C=NCHCO2Me] to Coordinated, Unsaturated Hydrocarbons of [(C6H7)Fe(CO)3]+, [C7H9Fe(CO)3]+, [(C7H7)M(CO)3]+ (M = Cr, Mo), and [(C2H4)Re(CO)5]+. α-Amino Acids with Organometallic Side Chains The addition of [Ph2C=NCHCO2Me] to [(C6H7)Fe(CO)3]+, [(C7H9)Fe(CO)3]+, [(C7H7)M(CO)3]+ (M = Cr, Mo) and [(C2H4)Re(CO)5]+ gives derivatives of α-amino acids with organometallic side chains. The structure of [(η4-C6H7)CH(N=CPh2)CO2Me]Fe(CO)3 was determined by X-ray diffraction. From the adduct of [Ph2C=NCHCO2Me] and [(C7H7)Mo(CO)3]+ the Schiff base of a new unnatural α-amino acid, Ph2C=NCH(C7H7)CO2Me, was obtained.  相似文献   

20.
Metal Sulfur-Nitrogen Compounds. 19. Novel Complexes of CuI with the S3N? Chelate Ligand. Preparation and Structure of [Ph4As][Cu(S3N)(CN)], [(Ph3P)2N][Cu(S3N)(S7N)], and [Ph4As]2[(S3N)Cu(S2O3)Cu(S3N)] In alkaline media S7NH reacts with Cu salts to yield different products. With Cu(CN) the ion [Cu(S3N)(CN)]? is formed, which was isolated as the [Ph4As]+ salt. The crystals are monoclinic, space group P21/c, a = 10.499(5), b = 13.418(6), c = 18.032(8) Å, β = 91.84°(3), Z = 4. Besides the known complex ions [Cu(S3N)2]? and [Cu(S3N)Cl]? still some more may be obtained when CuCl2 is reacted with S7NH: Under special conditions the S7N ring is partly preserved, and [Cu(S3N)(S7N)]? is formed. Its sparingly soluble [(Ph3P)2N]+ salt is monoclinic, space group P21/n, a = 9.335(6), b = 30.984(11), c = 15.108(8) Å, β = 102.87°(4), Z = 4. Using a longer reaction time a dinuclear complex [(S3N)Cu(S2O3)Cu(S3N)]? ? results from the reaction of CuCl2 with S7NH. The two Cu atoms are bridged by an S atom of the S2O3? ? anion. The [Ph4As]+ salt of the dinuclear complex anion is triclinic, space group P1 , a = 11.226(6), b = 12.423(6), c = 19.000(10) Å, β = 76.47°(4), β = 83.98°(4), γ = 84.71°(4), Z = 2. In all these compounds the coordination of CuI is trigonal-planar, the S3N? chelate group coordinates the Cu in the usual way by two S atoms.  相似文献   

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