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1.
Phosphoraneiminato Complexes of Hafnium. Crystal Structures of [Hf(NPPh3)4] · 3 THF and [Hf(NPPh3)2Cl2(HNPPh3)2] The phosphoraneiminato complexes [Hf(NPPh3)4] · 3 THF ( 1 · 3 THF) and [Hf(NPPh3)2Cl2(HNPPh3)2] ( 2 ) have been prepared as colourless, moisture sensitive single crystals by reactions of hafnium tetrachloride with [CsNPPh3]4 · 2 toluene in tetrahydrofurane solutions by application of different ratios of the educts. Both complexes are characterized by IR spectroscopy and X‐ray crystal structure determinations. 1 · 3 THF: space group P 1, Z = 4, lattice dimensions at 193 K: a = 2007.6(1); b = 2064.2(1); c = 2115.9(1) pm; α = 109.193(4)°; β = 111.285(4)°; γ = 96.879(4)°; R1 = 0.0506. 1 forms monomeric molecules with tetrahedral coordination of the nitrogen‐atoms of the (NPPh3)‐groups towards the Hafnium atom. The HfN distances of 200.9 pm in average correspond with double bonds. 2 : space group P 1, Z = 4, lattice dimensions at 193 K: a = 1444.0(1); b = 1928.1(1); c = 2455.8(2) pm; α = 67.273(8)°; β = 87.445(8)°; γ = 87.082(8)°; R1 = 0.0312. 2 has a monomeric molecular structure with octahedral coordination of the hafnium atom. The chlorine atoms are in trans position to one another, whereas the nitrogen atoms of the phosphoraneiminato groups (NPPh3) are in trans position towards the nitrogen atoms ot the phosphorane imine molecules (HNPPh3). The HfN bond lengths of the (NPPh3) groups of 199.7 pm in average correspond with double bonds, whereas the HfN distances of the HNPPh3 molecules with bond lengths of 230.2 pm in average are of donor‐acceptor type.  相似文献   

2.
The synthesis of second‐generation (G‐2) dendritic polymers of isoprene (I) and styrene (S) was achieved with anionic polymerization high‐vacuum techniques and by performing the following steps: (1) selective reaction of a living chain with the chlorosilane group of 4‐(chlorodimethylsilyl)styrene (a dual‐functionality compound) to produce a macromonomer, (2) addition of a second living chain (same or different) to the double bond of the macromonomer, (3) polymerization of I with the anionic sites, and (4) reaction of the produced off‐center living species with trichloromethyl silane or tetrachlorosilane (CH3SiCl3 or SiCl4). The combined characterization results showed that the G‐2 dendritic macromolecules synthesized—(S2I)3, (SI′I)3, (I″I′I)3, (I′2I)4—have a high molecular and compositional homogeneity. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1519–1526, 2002  相似文献   

3.
The reaction of 4‐amino‐1, 2, 4‐triazin‐3(2H)‐thione‐5‐one (ATTO, 1 ) with [Cu(PPh3)2]NO3 in ethanol led to the complex [Cu(PPh3)2(ATTO)]NO3 ( 2 ). 2 was characterized by elemental analyses, IR, 1H NMR and Raman spectroscopy. A single‐crystal X‐ray diffraction of compound 2 revealed that ATTO acts as a bidentate ligand via its nitrogen and sulfur atoms. Crystal data for 2 at 20 °C: space group P21/n with a = 975.7(1), b = 1533.5(2), c = 2504.2(3) pm, β = 92.25(1)°, Z = 4, R1 = 0.0632.  相似文献   

4.
The reaction of 4‐Amino‐6‐methyl‐1, 2, 4‐triazine‐3(2H)‐thione‐5‐one (AMTTO, 1 ) with silver nitrate in methanol led to the dimeric complex {[(AMTTO)2Ag]NO3}2 ( 2 ). 2 was characterized by elemental analyses and IR spectroscopy as well as by X‐ray structure analysis. Crystal data for 2 at ?80 °C: crystal system orthorhombic, space group P212121 with a = 1043.6(1), b = 1329.6(1), c = 2358.4(1) pm, Z = 8 and R1 = 0.037. The cation possesses a highly distorted linear coordination sphere in the solid state.  相似文献   

5.
The reaction of cadmium acetate in methanol with 1, 3‐bis(4‐nitrophenyl)triazene in THF in the presence of KOH yields K[Cd(O2NC6H4NNNC6H4NO2)3] in form of hexagonal prismatic, red crystals with the trigonal space group R3¯ and a = 12.229(2), c = 48.988(10) Å and Z = 6. In the anionic cadmium complexes, which are located along the threefold axis, the Cd atoms are coordinated in a trigonal prismatic arrangement by the atoms N(1) and N(3) of three triazenido ligands. The potassium cations are coordinated icosahedrally by oxygen atoms of each one nitro group of six neighbouring anionic complexes. The Cd‐N distances are 2.376(4) and 2.350(4) Å, and the K‐O distances are in the range of 2.833(6) to 3.365(6) Å.  相似文献   

6.
The new copper coordination polymers 2[CuX(μ‐2‐chlor‐opyrazine‐N, N')] (X = Cl ( I ), Br ( II ), 1[CuI(2‐chloropyrazine‐N)] ( III ) and [Cu2I2(2‐chloropyrazine)] ( IV ) has been prepared by the reaction of the copper(I) halides with 2‐chloropyrazine at roomtemperature or under hydrothermal conditions. The crystal structures of the 1:1 compounds I and II consist of zig‐zag CuX single chains running parallel to the crystallographic a‐axis which are linked by the 2‐chloropyrazine spacer molecules to sheets parallel to (010). For the iodine compound III a one‐dimensional structure is found which consists of CuX double chains running parallel to the crystallographic a‐axis. The thermic properties of all compounds were investigated in different gas atmospheres using simultaneously differential thermal analysis and thermogravimetry (DTA‐TG) as well as temperature resolved X‐ray powder diffraction. On heating, the 1:1 compounds I and II decompose directly to the corresponding copper(I) Halides, whereas the thermal decomposition of III occcur via IV as an intermediate.  相似文献   

7.
《中国化学》2018,36(8):712-715
Herein, two efficient palladium‐catalyzed intermolecular oxidative coupling reactions of (Z)‐enamines with isocyanides via selective β‐C(sp2)‐H and/or C=C bond cleavage have been developed, leading to controllable chemodivergent and stereoselective construction of a wide range of (E)‐β‐carbamoylenamine derivatives containing strong intramolecular hydrogen bonds. Furthermore, possible reaction pathways for these transformations are proposed on the basis of preliminary mechanism studies.  相似文献   

8.
[Fc2B2(Br)(μ‐NPEt3)2]+Br – a Ferrocenyl‐substituted Phosphoraneiminato Complex of Boron [Fc2B2(Br)(μ‐NPEt3)2]+Br has been prepared from ferrocenylboron dibromide, [Fe(η5‐C5H5)(η5‐C5H4BBr2)], and the silylated phosphoraneimine Me3SiNPEt3 in dichloromethane solution to give orange‐red single crystals which were characterized by IR, NMR and 57Fe Mössbauer spectra, as well as by a crystal structure determination. [Fc2B2(Br)(μ‐NPEt3)2]+Br · 3 CH2Cl2 ( 1 · 3 CH2Cl2): Space group P21/n, Z = 4, lattice dimensions at –50 °C: a = 1370.6(3), b = 2320.9(5), c = 1454.4(2), β = 95.38(1)°, R1 = 0.061. In the cation of 1 the ferrocenyl‐substituted boron atoms are connected by the nitrogen atoms of the [NPEt3] groups to form a planar B2N2 four‐membered ring. One of the boron atoms having planar, the other tetrahedral coordination.  相似文献   

9.
The zinc(II) center in the molecule of [(C23H36N4O3)ZnCl]Cl·H2O is coordinated by four nitrogen atoms of HL (1,3‐bis[2‐[2‐[(4‐methoxybenzyl) amino]ethylamino]]‐2‐propanol) and one chloro anion. The coordination moieties are connected by hydrogen bonds to form a one‐dimensional structure. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
The Reactions of Europium and Yttrium with N‐Iodinetriphenylphosphoraneimine. Crystal Structures of [EuI2(DME)3], [Eu2I(NPPh3)5(DME)] and [Y2I(NPPh3)4(THF)4]+I3 When treated with ultrasound, the reaction of europium metal with INPPh3 in 1,2‐dimethoxyethane (DME) leads to the complexes [EuI2(DME)3] ( 1 ) and [Eu2I(NPPh3)5(DME)] ( 2 ) which are separated from each other by fractional crystallization. On the other hand, the reaction of yttrium metal with INPPh3 under similar conditions in THF gives the ionic phosphoraneiminato complex [Y2I(NPPh3)4(THF)4]+I3 ( 3 ). All complexes are characterized by crystal structure determinations. 1 : Space group P21, Z = 2, lattice dimensions at 188 K: a = 848.9(1); b = 1059.4(1); c = 1227.9(1) pm; β = 93.793(6)°; R = 0.0246. In the molecular structure of 1 the europium atom is eightfold coordinated with a bond angle I–Eu–I of 158.51°. 2 · 2 DME: Space group P1, Z = 2, lattice dimensions at 193 K: a = 1405.5(1); b = 1652.2(2); c = 2203.7(2) pm; α = 89.404(11)°; β = 72.958(11)°; γ = 78.657(11)°; R = 0.0391. In 2 the europium atoms are linked by the μ‐N‐atoms of two (NPPh3) groups to form a planar Eu2N2 four‐membered ring. One of the Eu atoms is terminally coordinated by the N atoms of two (NPPh3) groups, thus achieving a distorted tetrahedral surrounding. The second Eu atom is coordinated by the N atom of one (NPPh3) group, by the terminally bounded iodine atom and by the oxygen atoms of the DME chelate, thus achieving a distorted octahedral surrounding. 3 · 61/2 THF: Space group P1, Z = 2, lattice dimensions at 103 K: a = 1739.7(2); b = 1770.1(2); c = 2153.8(3) pm; α = 74.929(15)°; β = 84.223(14)°; γ = 64.612(12)°; R = 0.0638. In the cation [Y2I(NPPh3)4(THF)4]+ of 3 the yttrium atoms are linked by the μ‐N atoms of two (NPPh3) groups as well as by the μ‐I atom. One (NPPh3) ligand and two THF molecules complete the distorted octahedral coordination at each yttrium atom.  相似文献   

11.
The crystal structure of EMIm diaquobis(μ‐oxalato)chromate(III) (1‐ethyl‐3‐methylimidazolium chromium(III) dioxalate dihydrate) was determined from X‐ray single crystal diffraction studies. A pale violet crystal of good optical quality was used for the structure determination at –100(2) and 25(2) °C. The basic crystallographic data for the low temperature structure are as follows: triclinic symmetry, space group P$\bar{1}$ , a = 7.6202(8) Å, b = 9.7668(9) Å, c = 10.7171(11) Å, α = 109.257(9)°, β = 90.494(8)°, γ = 105.685(8)°, V = 720.75(1) Å3. The crystal structure was solved by direct methods and refined (using anisotropic displacement parameters for all non‐hydrogen atoms) to a final residual of R1 = 0.039 for 2062 independent observed reflections [I > 2σ(I)]. The compound is built up from alternating layers parallel to (010) containing (EMIm)+ cations or Cr(C2O4)2(H2O)2 anions, respectively. The two crystallographically independent Cr(C2O4)2(H2O)2 octahedra reside on centers of symmetry (Wyckoff sites 1a and 1f). The corners of the octahedra consist of four oxygen atoms from two oxalate groups and two additional water molecules. EMIm+ cations provide linkage between different octahedral layers by hydrogen bridging. The water molecules in turn form hydrogen bonds with adjacent octahedra within the same layer. According to DTA/TG experiments the present compound shows several thermal processes in the range between room temperature and 1000 °C. However, pyrolysis is reproducibly yielding pure inorganic composites, qualifying this novel organic‐inorganic hybrid salt also as a stable precursor for nanoscalar ceramic materials. The final product consists of a distinct mixture of Cr2O3 and Cr3C2 in the molar ratio of 1:1. Concomittant oxide and carbide formation is an unprecedented disintegration pathway of the thermal treatment of oxalatochromates without reducing atmosphere.  相似文献   

12.
The compound [Cu42‐OH)23‐OH)2Cl2(bipy)4]Cl2 · 6H2O ( 1 ) was obtained by recrystallization of [Cu(HB)2(2, 2′‐bipy)] · H2O (H2B = diphenylglycolic acid) from EtOH/CH2Cl2 and their structure has been determined by single‐crystal X‐ray analysis. The cationic complex may be described as based on a Cu4(OH)4 core with a “stepped cubane” structure. The coordination polyhedron around each copper is a distorted square pyramid. The tetranuclear units are linked in the crystal by C‐H…Cl hydrogen bonds and by π‐π interactions between bipyridine rings. IR data are also presented.  相似文献   

13.
The Crystal Structures of (DDI)2[Sb2F6O] and (DDI)2[Sb3F7O2] (DDI = 1,3‐Diisopropyl‐4,5‐dimethylimidazolium) — a Contribution to the Hydrolysis of SbF3 [1] The salts (DDI)2[Sb2F6O] ( 2 ) and (DDI)2[Sb3F7O2] ( 3 ), (DDI = 1,3‐diisopropyl‐4,5‐dimethylimidazolium) are obtained by hydrolysis of C11H20N2SbF3 ( 1 ). The anion [Sb2F6O]2? consists of two SbF2 fragments linked by a symmetrical oxygen bridge and two unsymmetrical fluorine bridges to form a distored ψ‐octahedral coordination sphere at the antimony atoms. In [Sb3F7O2]2?, two SbF2 units are linked by a symmetrical fluorine bridge, while the third antimony atom is connected with each SbF2 fragment by a symmetrical oxygen and an unsymmetrical fluorine bridge. The antimony atoms adopt the centres of strongly distored ψ‐polyhedra.  相似文献   

14.
N‐sulfinylacylamides R‐C(=O)‐N=S=O react with (CF3)2BNMe2 ( 1 ) to form, by [2+4] cycloaddition, six‐membered rings cyclo‐(CF3)2B‐NMe2‐S(=O)‐N=C(R)‐O for R = Me ( 2 ), t‐Bu ( 3 ), C6H5 ( 4 ), and p‐CH3C6H4 ( 5 ) while N‐sulfinylcarbamic acid esters R‐O‐C(=O)‐N=S=O react with 1 to yield mixtures of six‐membered (cyclo‐(CF3)2B‐NMe2‐S(=O)‐N=C(OR)‐O) and four‐membered rings (cyclo‐(CF3)2B‐NMe2‐S(=O)‐N(C=O)OR) for R = Me ( 6 and 9 ), Et ( 7 and 10 ), and C6H5 ( 8 and 11 ). The structure of 5 has been determined by X‐ray diffraction.  相似文献   

15.
The title compounds 3‐5 are accessible by treatment of P(C6H4CH2NMe2)3( 1 ) with CuX ( 2a : X = Cl, 2b : X = Br, 2c : X = I) in the ratio of 1:1 or 1:2 in very good yields. Reaction of 1 with equimolar amounts of 2a affords the copper(I) chloride [P(C6H4CH2NMe2)3]CuCl ( 3 ). With a further equivalent of 2a homobimetallic [P(C6H4CH2NMe2)3]Cu2Cl2 ( 4 ) is formed, which also can be synthesized by the reaction of 1 with two equivalents of 2a. Complex 3 reacts with CuX (X = Br, I)to afford [P(C6H4CH2NMe2)3]Cu2ClX ( 5a : X = Br; 5b : X = I) in which mixed halides are present. The newly synthesized complexes 3‐5 were characterized by elemental analyses, by their IR‐, 1H‐, 13C{1H}‐ and 31P{1H}‐NMR spectra as well as by mass spectrometrical studies. The solid‐state structures of complexes 3 and 4 are reported. Mononuclear 3 crystallizes in the monoclinic space group P21/c with the cell parameters a = 14.285(2), b = 10.853(2), c = 17.425(2) Å , β = 103.310(10)?, V = 2628.9(7) Å 3 and Z = 4 with 4053 observed unique reflections; R1 = 0.0314. The crystal structure of 3 consists of monomeric molecules with planar coordinated copper(I) centres (CuClNP). Homobimetallic 4 crystallizes in the monoclinic space group P21/n with a = 23.905(4), b = 10.874(3), c = 25.314(5), β = 99.130(10)?, V = 6497(2) /Aring; 3 and Z = 4 with 9021 observed unique reflections; R1 = 0.0480. In 4 one of two copper(I) centres possesses a distorted trigonal‐pyramidal environment, while the other one is almost square‐pyramidal coordinated. The Cu2Cl2 segment resembles to a building block which is set up by a contact ion pair consisting of Cu+ and [CuCl2] , respectively.  相似文献   

16.
Dicarboxylate Groups as Ligands and Anions in Aquamagnesium Complexes: Crystal Structures of [Mg (C4H2O4)(H2O)4] · H2O and [Mg(H2O)6](C4HO4)2 · 2H2O ((C4H2O4)2— = Fumarate; (C4HO4) = Hydrogenacetylenedicarboxylate) Crystals of tetraaqua(fumarato)magnesium‐hydrate ( 1 ) and hexaaquamagnesium‐bis(hydrogenacetylenedicarboxylate)‐dihydrate ( 2 ) were prepared by reacting MgCl2 with sodium fumarate and acetylenedicarboxylic acid, respectively. In 1 cis‐Mg(H2O)4 units are bridged by α, Ö‐bonded fumarate groups. The resulting zig zag chains exhibit the maximum symmetry compatible with space group symmetry C2/c. 2 consists of layers of voluminous [Mg(H2O)6]2+ cations alternating with layers of C4HO4 anions. The nearly planar anions are held together by parallel stacking and by short hydrogen bonds. Both structures contain efficient H bridging systems. 1 : Space group C2/c, Z = 4, lattice constants at 20 °C: a = 5.298(1), b = 13.178(2), c = 13.374(2)Å; ß = 94.79(2)°, R1 = 0.024. 2 : Space group P1, Z = 1, lattice constants at 20 °C: a = 5.985(1), b = 6.515(1), c = 11.129(1)Å; α = 105.24(2), ß = 91.87(3), γ = 90.92(1)°, R1 = 0.034.  相似文献   

17.
18.
A suspension of CuX (X = Cl, Br) or AgCl in organic solvents (such as CH2Cl2) reacts with P(C7H7)3 ( 1 ) in a molar ratio 1:1 to give the mononuclear adducts CuX[P(C7H7)3] (X = Cl ( 2a ), Br ( 2b )) and AgCl[P(C7H7)3] ( 3a ) which crystallize as isotypic compounds in the orthorhombic space group Pnma (Z = 4). In the crystal, two (of the three) cyclohepta‐2, 4, 6‐trienyl substituents are present in the boat conformation, thus establishing a loose long‐distance interaction between the central double bond and the metal atom. A distorted pseudo‐tetrahedral coordination sphere is assumed to exist around the metal atom, with large P‐M‐X angles of 165.49(8)° ( 2a ), 162.07(7)° ( 2b ) and 168.54(3)° ( 3a ), respectively. The tetrameric 1:1 adduct {Cu(μ3‐I)[P(C7H7)3]}4( 2c ) which was obtained from CuI and 1 in boiling ethanol, has also been characterized by X‐ray crystallography (monoclinic space group P2(1)/n, Z = 4); it contains all 12 cyclohepta‐2, 4, 6‐trienyl substituents in the chair conformation. The NMR spectra (1H, 13C, 31P) of the new complexes 2a‐c and 3a indicate non‐rigid structures in solution. At room temperature, the 31P NMR signal of 3a appears as a doublet with an averaged coupling constant, 1J(Ag, P), of 700.1 Hz, whereas at —45 °C the two expected doublets are clearly discernible with coupling constants 1J(107Ag, 31P) = 671.0 Hz and 1J(109Ag, 31P) = 774.4 Hz, respectively.  相似文献   

19.
The complexes cis‐[SnCl4(H2O)2]·2H2O ( 1 ), [Sn2Cl6(OH)2(H2O)2]·4H2O ( 3 ), and [HL][SnCl5(H2O)]·2.5H2O ( 4 ) were isolated from a CH2Cl2 solution of equimolar amounts of SnCl4 and the ligand L (L=3‐acetyl‐5‐benzyl‐1‐phenyl‐4, 5‐dihydro‐1, 2, 4‐triazine‐6‐one oxime, C18H18N4O2) in the presence of moisture. 1 crystallizes in the monoclinic space group Cc with a = 2402.5(1) pm, b = 672.80(4) pm, c = 1162.93(6) pm, β = 93.787(6)° and Z = 8. 4 was found to crystallize monoclinic in the space group P21, with lattice parameters a = 967.38(5) pm, b = 1101.03(6) pm, c = 1258.11(6) pm, β = 98.826(6)° and Z = 2. The cell data for the reinvestigated structures are: [SnCl4(H2O)2]·3H2O ( 2 ): a = 1227.0(2) pm, b = 994.8(1) pm, c = 864.0(1) pm, β = 103.86(1)°, with space group C2/c and Z = 4; 3 : a = 961.54(16) pm, b = 646.29(7) pm, c = 1248.25(20) pm, β = 92.75(1)°, space group P21/c and Z = 4.  相似文献   

20.
A convenient one‐pot method for the preparation of (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones 2 and 3 from ethyl (2Z)‐3‐aryl‐2‐isothiocyanatoprop‐2‐enoates 1 , which can be easily prepared from ethyl 2‐azidoacetate and aromatic aldehydes, has been developed. Thus, these α‐isothiocyanato α,β‐unsaturated esters were treated with organolithium compounds, including lithium enolates of acetates, to provide 5‐substituted (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones, 2 , and 2‐[(4Z)‐(4‐arylmethylidene)‐5‐ethoxy‐2‐thioxo‐1,3‐oxazolidin‐5‐yl]acetates, 3 .  相似文献   

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