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1.
《Journal of Coordination Chemistry》2012,65(5):441-452
The reaction of CuX2(X=Cl, Br) with 2-aminopyrimidine in aqueous solution, or 2-amino-5-bromopyrimidine in aqueous acid yields compounds of the forms [LCuCl2] n (1), [L2CuCl2] (2) and [L'2CuBr2] (3) [L=2-aminopyrimidine; L'=2-amino-5-bromo-pyrimidine]. The three compounds all form layered structures in which each copper ion is coordinated to two 2-aminopyrimidine molecules and two halide ions. Common structural threads involve bridging ligation [either by monomeric (1) or hydrogen bonded ligand dimers (2 and 3)], N-H···X and N-H···N hydrogen bonding and π-π stacking interactions as well as semi-coordinate Cu···X bond formation (1 and 2) or Br···Br interactions (3). Compounds 1 and 2 crystallize as two-dimensional coordination polymers with asymmetrically bihalide bridged (CuX2) n chains cross-linked into sheets by the 2-aminopyrimidine molecules (1) or by hydrogen bonded L2 dimers (2). The halide bibridged chains expand their primary copper coordination spheres to give 4 + 2 coordination spheres in 1 and 2. In 3, the layer structure involves coordination of the hydrogen bonded L'2 dimers and C-Br···Br- interactions. Crystal data: (1): monoclinic, P21/m, a=3.929(1), b=12.373(2), c=7.050(1)å, β=91.206(4)°, V=342.7(1)Åsup3;, Z=2, D calc= 2.225Mg/m3, μ=3.878 mm-1, R=0.0269 for [|I|≥3σ(I)]. For (2): triclinic, P-1, a=4.095(4), b=7.309(5), c=10.123(6) å, α=86.28(6), β=78.44(6), γ=74.55(8)°, V=286.1(4) Å3, Z=1, D calc=1.884 Mg/m3, μ=2.360 mm-1, R=0.0506 for [|I|≥2σ(I)]. For (3): triclinic, P-1, a=6.074(4), b=7.673(3), c=8.887(3) å, α=108.43(3) β=100.86(5), γ=106.96(4)°, V=357.0(3) Å3, Z=1, D calc=2.657 Mg/m3, μ=12.714mm-1, R=0.0409 for [|I|≥2σ(I)]. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(7):795-803
The reaction of anhydrous CuCl2 with HCl and 2-amino-5-iodopyridine in 1-propanol resulted in two polymorphs of (5-IAP)2[CuCl4] [5-IAP = 2-amino-5-iodopyridinium], one as red rods (1) and one as orange prisms (2). The two polymorphs have been characterized by single crystal x-ray diffraction and variable temperature magnetic susceptibility. Crystal data: triclinic, P-1, F(000) = 606, MoK α (λ = 0.71073 Å): for (1): a = 9.248(6), b = 10.202(7), c = 10.368(7) Å, α = 102.451(9), β = 96.662(8), γ = 96.725(8)°, V = 938.4(11) Åsup3;, Z = 2, Dcalc = 2.291 Mg/m3, μ = 5.020 mm?1, R = 0.0392 for [|I|≥2σ(I)]. For (2): a = 8.966(2), b = 10.755(2), c = 11.359(2) Å, α = 89.63(3), β = 68.04(3), γ = 69.07(3)°, V = 938.6(3) Åsup3;, Z = 2, D calc = 2.291 Mg/m3 , μ = 5.019 mm?1 , R = 0.0217 for [|I|≥2σ(I)]. The crystal packing for both polymorphs suggests that their magnetic behavior should be that of weakly interacting alternating linear chains. Temperature dependent susceptibility measurements yield: for 1 , C = 0.43, g = 2.14, θ = m 1.98; for 2, C = 0.45, g = 2.19, θ = ?4.15. 相似文献
3.
《Journal of Coordination Chemistry》2012,65(1-2):11-17
Abstract Reaction of Cu(ClO4)2·6H2O with 1,3,5-triazine in 95% ethanol resulted in partial hydrolysis of the triazine ring and isolation of bis(1,3,5-triaza-1,4-pentadieno) copper(II) perchlorate, (1). Compound 1 crystallizes as violet needles. Crystal data for Cu(HN = CHNHCH = NH)2(ClO4)2 are: monoclinic, space group: C2/c, a = 13.342(3), b = 11.186(2), c = 18.045(4) Å, β = 99.09(3)°, V = 2659.3(10) Å3, Z = 8, Dcalc = 2.021 Mg/m3, μ = 2.096 mm?1, F(000) = 1624, MoKα (γ = 0.71069Å), R = 0.063 for 1597 unique observed [≥Fα3σ(F)] reflections and 196 parameters. The bis-chelated copper(II) ion contains a planar coordination geometry with Cu-N(ave) = 1.97Å and the perchlorate ions weakly coordinated (Cu - 0 = 2.84Å) in the axial positions. 相似文献
4.
Biao Wu Peiju Yang Xiaojuan Huang Yanyan Liu Xiaofei Liu Chungu Xia 《无机化学与普通化学杂志》2006,632(4):684-688
The complexes [Cu(dpp)Br2] ( 1 ) and [Cu(dpp)2][CuBr2] ( 2 ) (dpp = 2,9‐diphenyl‐1,10‐phenanthroline) were synthesized and characterized by single‐crystal X‐ray diffraction methods. Reaction of copper(II) bromide with the dpp ligand in dichloromethane at room temperature afforded 1 , which is a rare example of non‐square planar four‐coordinate copper(II) complexes. Complex 1 crystallizes in the monoclinic space group C2/c with a = 15.352(3), b = 13.192(3), c = 11.358(2) Å, β = 120.61(3)°, V = 1979.6(7) Å3, Z = 4, Dcalc = 1.865 g cm?3. The coordination geometry about the copper center is distorted about halfway between square planar and tetrahedral. The Cu‐N distance is 2.032(2) Å and the Cu‐Br distance 2.3521(5) Å. Heating a CH2Cl2 or acetone solution of 1 resulted in complex 2 , which consists of a slightly distorted tetrahedral [Cu(dpp)2]+ cation and a linear two‐coordinate [CuBr2]? anion. 2 crystallizes in the triclinic space group with a = 10.445(2), b = 11.009(2), c = 18.458(4) Å, α = 104.72(3), β = 94.71(3), γ = 103.50(3)°, V = 1973.3(7) Å3, Z = 2, Dcalc = 1.602 g cm?3. The four Cu(1)‐N distances are between 2.042(3) and 2.067(3) Å, the distance of Cu(2)‐Br(1) 2.2268(8) Å, and the disordered Cu(3)‐Br(2) distances are 2.139(7) and 2.237(4) Å, respectively. Complex 2 could also be prepared by directly reacting CuBr with dpp in CH2Cl2. 相似文献
5.
G. V. Romanenko Z. A. Savelyeva N. V. Podberezskaya V. I. Alekseev S. V. Larionov 《Journal of Structural Chemistry》1994,35(3):317-323
Synthesis and structure of a novel thermochromic complex (CH8N4)2[CuCl6] are reported. X-ray analysis of the compound was carried out for a single crystal 0.4×0.2×0.05 mm in size (a bright-yellow plate). The monoclinic unit cell parameters are a=7.167(1), b=15.561(3), c=7.328(1) Å, β=118.73(3)°, V=716.7(2) Å3, space group P21, Z=2 (CH8N4)2[CuCl6] dcalc=1.99 g/cm3, μ(MoKα)=2.65 mm?1, R=0.0264, and Rw=0.0290 for 1411 Ihkl>2σI. 相似文献
6.
Single crystals of two new modifications of [P(C6H5)4]2[Cu2I4] were obtained by reaction of granulated copper with iodine and [P(C6H5)4]I in dry acetone under nitrogen atmosphere. They crystallise monoclinically, space group P21/n (No. 14), a = 11.550(6), b = 7.236(2), c = 27.232(13) Å, β = 98.13(3)°, V = 2253(2) Å3, and Z = 2 ([P(C6H5)4]2[Cu2I4]-C), and space group Cc (No. 9), a = 17.133(5), b = 15.941(5), c = 18.762 (6) Å, β = 114.02(1)°, V = 4681(3) Å3, and Z = 4 ([P(C6H5)4]2[Cu2I4]-D), respectively. In these compounds the [CuI2]? anions form dimers di-μ-iodo-diiodocuprate(I), which are either planar ( C ) or folded ( D ). 相似文献
7.
Abstract The crystal structure of a complex formed between La(III) and p-sulfonatocalix[4]arene is reported. The complex cristallizes in the monoclinic space group P21/n, a = 15.091(1), b = 28.550(3), c = 30.167(3) Å, β = 90.008(2)°, V = 12997(2) Å3, ρcalc. (g cm?3) = 1.792, Z = 2. Refinement led to R1 value of 0.0961 for 13930 unique reflections. It forms discrete units with 8 La(III) cations coordinated by 6 calixarene ligands. The calixarenes are organized in an up-down configuration, bridged by La(III), forming layers of 3 repeating calixarene units and channels along the a axis. The units are linked by hydrogen-bonds. 相似文献
8.
Yue-Qing Zheng Horst Borrmann Yuri Grin Karl Peters Hans Georg von Schnering 《无机化学与普通化学杂志》1999,625(12):2115-2119
The reaction of W6Br12 with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W6Br14] ( I ) and yellowish green platelets of Ag2[W6Br14] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P21/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W6Bri8)Bra6]1– and [(W6Bri8)Bra6])]2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Bri) = 2.617 Å, d(W–Bra) = 2.575 Å, d(Bri…Bri) = 3.700 Å, d(Bri…Bra) = 3.692 Å, ∠W–Bri–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Bri) = 2.624 Å, d(W–Bra) = 2.613 Å, d(Bri…Bri) = 3.710 Å, d(Bri…Bra) = 3.707 Å, ∠W–Bri–W = 60.23°. The Ag+ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W6Br14] anions will be discussed. 相似文献
9.
《Journal of Coordination Chemistry》2012,65(4):393-402
The reaction of CuCl2 with 2-amino-5-cyanopyridine and HCl in 1-propanol gave bis(2-amino-5-cyanopyridinium) diaquadichlorocopper(II) dichloride (1). Crystal data for 1 are: monoclinic, space group: P21/c, a = 8.461(3) Å, b=14.665(5) Å, c=7.883(3) Å, g =96.105(4)°, V=972.6(6) Å 3 , Z=2, Dcalc =1.645 Mg/m3, w =1.691 mm?1, F(OOO)=486, MoK f( u =0.71073 Å), R1=0.0431 for [∣I∣ S 2 σ (I)] and R1=0.0680 for all 1944 unique reflections and 130 parameters. The structure exists as square planar Cu(H2O)2Cl2 units with long semi-coordinate bonds to the cyano nitrogens of the 2-amino-5-cyanopyridinium ions. Hydrogen bonding from the water molecules and N―H hydrogens to the chloride irons stablises the lattice. 相似文献
10.
《Journal of Coordination Chemistry》2012,65(7):563-570
Reaction products of Cu(II) 2-chlorobenzoate and 4-aminopyridine (1), and of Cu(II) 2,6-dichlorobenzoate and 4-aminopyridine (2) formulated as CuL′2(4-apy)2 and CuL″2(4-apy)2((L′ =C7H4ClO? 2,L″ =C7H3Cl2O? 2, 4-apy = 4-aminopyridine), were prepared and characterized by structural and spectroscopic measurements, thermochemical properties and magnetic susceptibilities. Compound (1) crystallizes in the orthorhombic space group Pbca, a = 8.875(2), b = 13.236(4), c = 21.603(3) Å, V = 2537.7(10) Å3, Z = 4, and the Compound (2) crystallizes in the monoclinic space group P21/c, a = 11.516(2), b = 8.749(2), c = 13.469(3) Å, β = 103.36(3)°, V = 1320.3(5) Å3, Z = 2. Complexes (1) and (2) decomposes to gaseous products at 473 and 513 K, respectively. 相似文献
11.
《Journal of Coordination Chemistry》2012,65(12):1427-1431
The synthesis and structural characterization of a novel In(III) complex is described. The reaction between InCl3 with sodium mercapto-acetic acid (NaSCH2(CO)OH) in 4-methylpyridine (CH3(C5H5N), (4-Mepy)) at 25°C affords [ClIn(SCH2(CO)O)2]2-[(4-MepyH)2]2+ (1). X-ray diffraction studies of (1) show it to have a distorted square-pyramidal geometry with the [(-SCH2(CO)CO-)] ligands in a trans conformation. The compound crystallizes in the P1(No. 2) space group with a = 7.8624(6) Å, b = 9.950(1) Å, c = 13.793(2) Å, α = 107.60(1)°, β = 90.336(8)°, γ = 98.983(9)°, V = 1014.3(4) Å3, R(F°) = 0.037 and Rw = 0.048. 相似文献
12.
Brown crystals of [PPh4]2[Se2Br6] ( 1 ) and [PEtPh3]2[Se2Br6] ( 2 ) were obtained when selenium and bromine reacted in acetonitrile solution in the presence of tetraphenylphosphonium bromide and ethyltriphenylphosphonium bromide, respectively. The crystal structure of 2 has been determined by X‐ray methods and refined to R = 0.0420 for 4161 reflections. The crystals are monoclinic, space group P21/n with Z = 2 and a = 13.055(3) Å, b = 12.628(3) Å, c = 13.530(3) Å, β = 92.40(3)° (293(2) K). In the solid state structure of 2 the dinuclear hexabromo‐diselenate(II) anion is centrosymmetric and consists of two distorted almost square‐planar SeBr4 units sharing a common edge through two bridging Br atoms. The terminal SeII–Br bond distances are found to be 2.419(1) and 2.445(1) Å, the bridging μBr–SeII bond distances 2.901(1) and 2.802(1) Å. 相似文献
13.
The reaction of W6Br12 with CuBr sealed in an evacuated silica tube at the temperature gradient 925/915 K and annealing at 625/300 K yields a mixture of orthorhombic α-Cu2[W6Br14] and cubic β-Cu2[W6Br14] in the low temperature zone. α-Cu2[W6Br14] crystallizes in the space group Pbca (no. 61), a = 15.126 Å, b = 9.887 Å, c = 15.954 Å, Z = 4, oP88, and β-Cu2[W6Br14] crystallizes in the space group Pn3 (no. 201), a = 13.391 Å, Z = 4, cP88. The crystal structures are built up by [(W6Br)Br]2– cluster anions and Cu+ cations. The cluster anions show only in the peripheral shells small deviation from m3m symmetry (d(W–W) = 2.630 Å; d(W–Bri) = 2.618 Å; d(W–Bra) = 2.614 Å). The anions are arranged in a slightly compressed bcc pattern (α) and ccp (β) pattern, respectively. The Cu+ cations are trigonal-planar coordinated by Bra ligands with d(Cu–Br) = 2.377 Å (α) and 2.378 Å (β). The cubic β-modification is diamagnetic with an unexpected large susceptibility (χmol = –884 × 10–6 cm3 mol–1) and have a band gap of 2.8 eV. It decomposes under dynamic vacuum in two steps at 795 K und 1040 K. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(13):2296-2306
Two cadmium(II) coordination polymers, [Cd(2-mBIM)(NCS)(SCN)] n (1) and [Cd2(2-mBIM)2(NO3)2(C4H4O4)(H2O)5] n (2) (2-mBIM = bis(2-methylimidazo-1-yl)methane, C4H4O4= succinate), have been synthesized and characterized by X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 with a = 9.0770(5) Å, b = 9.4043(4) Å, c = 19.8720(9) Å, α = 101.551(1)°, β = 93.498(1)°, γ = 108.484(1)°, V = 1562.02(13) Å3, and Z = 2. Each Cd(II) is octahedrally coordinated and connected with two adjacent Cd(II)'s by double end-to-end thiocyanate bridges, resulting in the formation of 1-D zigzag chains, linked to each other via bridging 2-mBIM giving a 2-D supramolecular framework. Complex 2 crystallizes in the monoclinic space group P2(1)/n with a = 12.6543(6) Å, b = 7.7128(4) Å, c = 17.3089(9) Å, β = 109.3980(10)°, V = 1593.45(14) Å3, and Z = 2. Cd(II) is coordinated with oxygen and nitrogens from two independent 2-mBIM, in a cis-configuration to form a 1-D helical structure. A 3-D supramolecular network comprised of succinate anion bridged 1-D helical chains, and weak hydrogen bonds between dimer waters gave 2-D layers. 相似文献
15.
A. V. Virovets M. Laege B. Krebs O. A. Geras'ko V. E. Fedorov O. V. Shishkin Yu. T. Struchkov 《Journal of Structural Chemistry》1996,37(4):666-673
Crystal structures of (Et4N)2[Mo3S7Br6] (I) and (Et4N)(H9O4)[Mo3S7Cl6] (II) clusters belonging to the class of Mo3S 7 4+ were determined by X-ray diffraction analysis. Crystals I are orthorhombic a=19.106(3), b=12.930(2), c=29.887(5) Å, V=7383(2) Å3, space group Pbca, Z=8, dcalc=2.253 g/cm3, R(F)=0.0402, wR(F2)=0.0587 for 2493 Fhkl>4σ. Crystals II are monoclinic, a=17.106(3), b=18.882(4), c=11.006(2), Å, β=126.13(3)°, V=2871.2(9) Å3, space group Cc, Z=4, dcalc=2.147 g/cm3, R(F)=0.0181, wR(F2)=0.0445 for 2307 Fhkl>4σ. Structure I has an anion dimer with 3Sax…Cl=3.258(4)–3.404(4) Å; the dimer is similar to that observed in the structures of A2[M3X7Hal6], A=Ph4P+, Ph3EtP+, and PPN+. In structure II, infinite chains of anions bonded by 3Sax…Cl contacts of 3.183(3)–3.394(3) Å were found. A similar phenomenon was established earlier for the structure of (Et4N)(H9O4)[Mo3S7Br6] (III), which is not isostructural to II. Compounds II and III also differ in the structure of the H9O4 + cation: infinite helix in II and pyramid in III. 相似文献
16.
Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl, Br, NO3) cocrystallize in aqueous solutions of [Ta6Br12]2+ in the presence of Cu2+ ions. The crystal structures of [Ta6Br12(H2O)6]Cl2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 1 ) and [Ta6Br12(H2O)6]Br2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta6Br12]2+ in the [Ta6Br12(H2O)6]2+ cation and [Ta6Br12]4+ in trans‐[Ta6Br12(OH)4(H2O)2]. Average bond distances in the [Ta6Br12(H2O)6]2+ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Bri , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Bri , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta6‐Br12(OH)4(H2O)2]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Bri, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H2O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Bri, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H2O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta6Cl12]2+ oxidized to [Ta6Cl12]4+ , whereas [Nb6X12]2+ clusters were not affected by the Cu2+ ion. 相似文献
17.
A. V. Virovets I. A. Baidina V. I. Alekseev N. V. Podberezskaya L. G. Lavrenova 《Journal of Structural Chemistry》1996,37(2):288-294
The crystal structure of the dichlorobis(1-allyltetrazole-N4)copper(II) complex was determined by X-ray diffraction analysis. The crystals are monoclinic, a=14.233(3), b=6.755(1), c=7.273(1) Å, β=104.63(3)°, Vcell=676.6(2), Å3, space group P21/c, Z=4, dcalc=1.741g/cm3, dmsd=1.69 g/cm3, CAD-4, λMoKα radiation, RF=0.0377 for 520 Fhkl>4σ(Fhkl) and 0.0560 for all 872 independent reflections. The structure is layered; the coordination polyhedron of copper is a square bipyramid, in which the equatorial positions are occupied by two chlorine atoms (Cu?Cl 2.27(2)–2.31(2) Å) and two N4 atoms of planar tetrazole ligands, whereas the axial positions are occupied by two chlorine atoms of the neighboring molecules of the complex (Cu?Cl 2.97(2)–3.01(2) Å). The sublattice of chlorine atoms is disordered in such a way that the [CuCl4/2]∞∞ layer is a superposition of two variants with weights 61(3) and 39(3)% and with similar geometrical characteristics: the equatorial chlorine atoms in variant A are replaced by the axial atoms in variant B and vice versa. The tetrazole ligand has the same position in both variants. In general, the crystal is a polytype with random alternation of A and B type blocks. It is shown that the compound is isostructural to the complex with 1-ethyltetrazole [Cu(ettz)2Cl2], in which only variant B is realized. 相似文献
18.
Grigorii A. Tikhomirov Konstantin O. Znamenkov Igor V. Morozov Erhard Kemnitz Sergei I. Troyanov 《无机化学与普通化学杂志》2002,628(1):269-273
Crystalline NO[Mn(NO3)3] ( I ) and (NO)2[Co(NO3)4] ( II ) were synthesized by reaction of the corresponding metal and a liquid N2O4/ethylacetate mixture. I is orthorhombic, Pca21, a = 9.414(2), b = 15.929(3), c = 10.180(2) Å, Z = 4, R1 = 0.0286. II is monoclinic, C2/c, a = 14.463(3), b = 19.154(4), c = 13.724(3) Å, β = 120.90(3), Z = 12, R1 = 0.0890. Structure I consists of [Mn(NO3)3]– sheets with NO+ cations between them. Two types of Mn atoms have CNMn = 7 and 8. Structure II is ionic containing isolated [Co(NO3)4]‐anions and NO+ cations with CNCo = 8. Crystals of Mn(NO3)2 ( III ) and Co(NO3)2 ( IV ) were obtained by concentration of metal nitrate hydrate solutions in 100% HNO3 in a desiccator with P2O5. III is cubic, Pa 3, a = 7.527(2) Å, Z = 4, R1 = 0.0987. IV is trigonal, R 3, a = 10.500(2), c = 12.837(3) Å, Z = 12, R1 = 0.0354. The three dimensional structure III is isotypic to the strontium and barium dinitrates. Structure IV contains a three dimensional network of interconnected Co(NO3)6/3 units with a distorted octahedral coordination environment of Co atoms. General correlations between central atom coordination and coordination modes of NO3 groups are discussed. 相似文献
19.
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
20.
Brown crystals of [NMe4]4[(Se4Br10)2(Se2Br2)2] ( 1 ) were obtained from the reaction of selenium and bromine in acetonitrile in the presence of tetramethylammonium bromide. The crystal structure of 1 was determined by X‐ray diffraction and refined to R = 0.0297 for 8401 reflections. The crystals are monoclinic, space group P21/c with Z = 4 and a = 12.646(3) Å, b = 16.499(3) Å, c = 16.844(3) Å, β = 101.70(3)° (123 K). In the solid‐state structure, the anion of 1 is built up of two [Se4Br10]2– ions. Each shows a triangular arrangement of three planar SeBr4 units sharing a common edge through two μ3‐bridging bromine atoms, and one SeBr2 molecule, which is linked to the SeII atoms of two SeBr4 units; between the Se4Br102– ions a dimerized Se2Br2 molecule (Se4Br4) is situated and one SeI atom of each Se2Br2 molecule has two weak contacts [3.3514(14) Å and 3.3952(11) Å] to two bromine atoms of one SeBr4 unit. Four SeI atoms of a dimerized Se2Br2 molecule are in a almost regular planar tetraangular arrangement. Contacts between the SeII atom of the SeBr2 molecule and the SeII atoms of two SeBr4 units are 3.035(1) Å and 3.115(1) Å, and can be interpreted as donor‐acceptor type bonds with the SeII atoms of SeBr4 units as donors and the SeBr2 molecule as acceptor. The terminal SeII–Br and μ3‐Br–SeII bond lengths are in the ranges 2.3376(10) to 2.4384(8) Å and 2.8036(9) to 3.3183(13) Å, respectively. The bond lengths in the dimerized Se2Br2 molecule are: SeI–SeI = 2.2945(8) Å and 3.1398(12), SeI–Br = 2.3659(11) and 2.3689(10) Å. 相似文献