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991.

Abstract  

The reaction of N-[(S)-1-phenylethyl]-N-[1-(2-pyridinyl)methyl]amine (PEPMA) with Zn(ClO4)2 affords (PEPMA)2Zn(ClO4)2 at room temperature. The complex is characterized by elemental analysis, 1H-MNR and X-ray crystallography. The crystal system is orthorhombic with space group of P212121 and unit cell parameters: a = 8.6911(4), b = 9.7755(7), c = 37.275(2) ?, V = 3166.9(3) ?3, Z = 4, D x  = 1.445 Mg/m3. The crystal structure reveals that zinc metal is ligated by two PEPMA ligands in a distorted tetrahedral fashion. Interestingly, both nitrogen atoms of amine at PEPMA to the central zinc metal exhibit (R)-configuration.  相似文献   
992.

Abstract  

Schiff base (E)-2-[(benzo[d]thiazol-2-ylimino)methyl]phenol (1) has been synthesized from the reaction of 2-hydroxy-benzaldehyde with 2-aminobenzothiazole. The 2-[(benzo[d]thiazol-2-ylamino)methyl]phenol (2) was prepared reduction of the Schiff base 1 with sodium borohydride. The compounds 1 and 2 have been characterized by elemental analysis, FT-IR, 1H-NMR, 13C-NMR and UV–visible spectroscopic techniques. The structure of the compound 2 has also been examined crystallographically. The compound 2 crystallizes in the monoclinic space group P2/c. The unit cell parameters were found as a = 10.017(1), b = 11.725(1), c = 10.341(1) ?, V = 1208.1(1) ?3, D x = 1.409 g cm−3 and Z = 4. The crystal structure was solved by direct methods and refined by the full-matrix least squares method and found as R 1 = 0.0308 and wR 2 = 0.0818 for 2032 for the observed reflections [I > 2σ(I)].  相似文献   
993.
[1,2,3-13C3]-1-(Phenylsulfinyl)-3-benzyloxyacetone, C16H16O3S, (3) has been synthesized and its crystal structure has been determined by a single-crystal X-ray diffraction analysis. The X-ray diffraction study revealed that compound 3 crystallizes in the monoclinic crystal system in the acentric space group Pc, with cell constants at T = 100 K: a = 16.073(5), b = 5.5079(16), c = 7.949(2) Å, β = 100.221(4)°, V = 692.6(3) Å3, Z = 2, d calc = 1.383 g/cm3. Compound 3 contains the chiral tetravalent three-coordinated sulfur atom, which has a distorted tetrahedral configuration with a lone electron pair occupying one of the tetrahedron vertices. In the crystal, the molecules are packed in stacks along the b axis; the stacks consist of the molecules of the same chirality. Furthermore, the stacks of the molecules of the opposite chirality alternate along the c axis. The molecules in neighboring stacks are arranged by head-to-tail orientations. There are no short intermolecular contacts in the crystal of 3.  相似文献   
994.
Abstract The X-ray crystal structure of the complex formed between 5,5′-bipyrimidine and C-methylresorcinarene is described. The structure (C41H45N5O12) is triclinic with a = 12.8610(10), b = 13.0560(10), c = 13.6068(11)?, α = 104.0730(10), β = 104.9260(10), γ = 111.6430(10)° and space group P-1. The structure reveals that the resorcinarene adopts a boat conformation and forms a three-dimensional network through hydrogen bonding to two water molecules and one dipyrimidine ligand. A single nitromethane molecule is included in the superstructure. Graphical Abstract Self-Assembly of C-Methyl Calix[4]resorcinarene with 5,5’-Bipyrimidine Charles L. Barnes(1) and Eric Bosch(2)* The X-ray crystal structure of the complex formed between 5,5′-bipyrimidine and C-methylresorcinarene is reported.   相似文献   
995.
Abstract One new mononuclear manganese complex of [Mn(4,4′-bip)2(OH2)4](DBA) · 4H2O (1) (4,4′-bipyridine, 4,4′-bip; H2DBA, benzene-1,3-dicarboxylic acid) has been obtained from the hydrothermal reaction of MnCl2 · 4H2O, 4,4′-bipyridine and H2DBA in the solvent of H2O at 140 °C for 3 days, characterized by X-ray analysis, spectroscopic methods, and thermal analysis. Packing diagram shows that the three-dimensional network was formed via hydrogen bonds and strong π–π interactions. Graphical abstract One Novel Three-dimensional Network Constructed from [Mn(4,4′-bip) 2 (OH 2 ) 4 ] 2+ Cations and DBA 2− Anions via Hydrogen-bonding and π–π Interactions Ying Liu, Bao Zhang, Jian-min Dou, Da-qi Wang, Da-cheng Li, Lei Zhou One new mononuclear manganese complex of [Mn(4,4’-bip)2(OH2)4](DBA) · 4H2O (1) (4,4’-bipyridine, 4,4’-bip; H2DBA, benzene-1, 3-dicarboxylic acid) has been obtained and haracterized by X-ray analysis, spectroscopic methods, and thermal analysis. Packing diagram shows that the three-dimensional network was formed via hydrogen bonds and strong π-π interactions.   相似文献   
996.
Cu(II) and Pb(II) complexes of 4,4′-bipyridine-N,N′-dioxide have been prepared using a solvent-layering system. [Cu2Cl4(bpdo)3(H2O)2] . 2(CH3)2SO (1) crystallises in P-1, a=8.731(2), b=8.943(2), c=14.408(3) ?, α=102.85(3), β=97.49(3), γ=109.77(3)°. The Cu(II) complex is a z-shaped discrete molecule with a DMSO molecule hydrogen bonded to the host through coordinated water molecule. Crystallisation of PbCl2, PbBr2 and PbI2 with bpdo afforded isostructural 2D coordination polymers. [PbCl2(bpdo)]n is monoclinic, C2/c with a=16.3274(7), b=4.0708(1), c=18.6146(8) ?, β=93.73(1)°; [PbBr2(bpdo)]n is monoclinic, C2/c with a=16.403(3), b=4.2412(8), c=18.846(4) ?, β=92.59(3)° and [PbI2(bpdo)]n is monoclinic, C2/c with a=16.438(3), b=4.538(1), c=18.973(4) ?, β=91.04(3)°. The adjacent metal centres of these polymers are bridged by coordinated Cl, Br or I anions as well as by bpdo ligands. These polymers possess no conventional hydrogen bonds.  相似文献   
997.
Four phosphonium rhenates(VII) were prepared and crystallized: (A) 1,2-bis (triphenylphosphonium)ethane rhenate(VII) (Pī, a=8.298(2), b=10.638(3), c= 11.242(3) ?, α=64.96(2), β=80.49(2), γ=88.17(2)°), (B) methyltriphenylphosphonium rhenate(VII) (Pca21, a=15.096(3), b=12.627(3), c=19.353(3) ?), (C) benzyltriphenylphosphonium rhenate(VII) (Pī, a=9.648(2), b=11.689(2), c=20.806(3) ?, α=88.44(2), β=84.63(2), γ=77.33(3)°), and (D) orthorhombic form of (iodomethyl)triphenylphosphonium rhenate(VII) (Pca21, a=14.952(3), b=13.120(3), c=20.603(4) ?). Each crystal structure consists of separate phosphonium cations and rhenate(VII) anions. In A centrosymmetric 1,2-bis(triphenylphosphonium)ethane cations form layers perpendicular to [011]. In B the cations are set in chains along [100] forming layers perpendicular to [001]. In C two symmetrically-independent cations form double columns along [100] and these columns are arranged in puckered layers perpendicular to [001]. D is almost isomorphous to B. The crystal structures are stabilised by weak C–H⋯O hydrogen bonds as well as phenyl rings interactions. In all crystal structures supramolecular motifs of phenyl rings embraces could be distinguished.  相似文献   
998.
The crystal structures of [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][TaF6] and [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] complex compounds are determined using X-ray diffraction analysis. The tantalum complex has two polymorphic modifications, namely, the monoclinic (I) and triclinic (II) modifications. The unit cell parameters of these compounds are as follows: a = 8.507(4) Å, b = 11.947(5) Å, c = 27.392(12) Å, β = 93.11(1)°, Z = 4, and space group P21/n for modification I; and a = 10.828(1) Å, b = 11.204(1) Å, c = 12.378(1) Å, α = 72.12(1)°, β = 79.40(1)°, γ = 73.70(1)°, Z = 2, and space group P-1 for modification II. The triclinic niobium complex [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] (III) with the unit cell parameters a = 10.796(3) Å, b = 11.183(3) Å, c = 12.352(3) Å, α = 72.364(5)°, β = 79.577(5)°, γ = 73.773(4)°, Z = 2, and space group P-1 is isostructural with tantalum complex II. The structures of all three complexes are ionic in character. The oxonium cation in complexes I–III is encapsulated by the crown ether and thus forms one ordinary and two bifurcated hydrogen bonds with the oxygen atoms of the crown ether. This macrocyclic cation is bound to the anions through the C-H...F contacts (H...F, 2.48–2.58 Å). The conformation of the macrocycle in complex I differs substantially from that in complex II (III).  相似文献   
999.
An oxamido-bridged binuclear copper(II) complex, Cu2(oxen)(NCS)2(DMF)2 (1) (H2oxen = N,N′-bis(2-aminoethyl)oxamide, DMF = dimethylformamide), has been synthesized by the reaction of Cu(oxen) · 2H2O with CuCl2 · 2H2O and KSCN in DMF/CH3OH solution, and characterized by elementary analysis, FT-IR spectra and X-ray single-crystal diffraction. Structural analysis reveals that complex 1 forms a centrosymmetric binuclear molecule in which an oxamido group in the trans conformation bridges two crystallographically equivalent five-coordinate copper(II) ions with Cu–Cu distance of 5.279(2) Å. The complex molecules are assembled into a novel 2D layer through weak Cu?S interactions (d Cu–S = 3.341(4) Å) and intermolecular hydrogen bonds. Viewed along the crystallographic b axis, layers display an interesting hydrophobic–hydrophilic–hydrophobic sandwich arrangement, with the hydrophobic layers dominated by dipole interaction of DMF molecules.  相似文献   
1000.
The synthesis and molecular structure of the novel 1-[ferrocenyl(hydroxy)methyl]-1,7-dicarba-closo-dodecaborane (1) is described. Compound 1 was synthesized from reaction of m-carborane and ferrocene carboxaldehyde using n-butyllithium (n-BuLi) or tetrabutylammonium fluoride (TBAF) in THF in 45% and 36% yield, respectively. Compound 1 consists of a ferrocene molecule tethered to m-carborane through a methylhydroxy bridge. The crystal structure of 1 was determined by single crystal X-ray diffraction analysis. Crystal data: 1 [Fe(C5H5)(C5H4-CH2O-1,7-C2B10H12)], formula weight = 359.17, crystallized in orthorhombic system, space group Pna2 1 with a=19.698(4) ?, b=10.709(2) ?, c=8.520(2) ?, and V=1797.3(7) ?3 and Z=4. Refined to R 1=0.043 for 4124 observed reflections with I/σ>2σ(I). The compound was crystallized as racemic twins in a ratio of 73(2)/27(2). The unsubstituted Cp ring was disordered and modeled as two conformations in a 53(3)/47(3) ratio. Intermolecular hydrogen bonding was observed from the hydrogen of the meta-carbon on the carborane cluster towards the hydroxyl oxygen.  相似文献   
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