Structures of Ionic Di(arenesulfonyl)amides. 3. Four Sodium Di(arenesulfonyl)amides: Lamellar Layers Exhibiting Short C–H…O(nitro), C–H…F–C, or C–I…I–C Interlayer Contacts Low‐temperature X‐ray crystal structures are reported for NaN(SO2C6H4‐4‐X)2 · n H2O, where X = NO2 and n = 3 ( 1 , monoclinic, space group P21, Z = 2), X = F and n = 3 ( 2 , monoclinic, P21/c, Z = 4), X = F and n = 1 ( 3 , orthorhombic, Pccn, Z = 8), or X = I and n = 1 ( 4 , monoclinic, P21/c, Z = 4). The four compounds are examples of layered inorgano‐organic solids where the inorganic component is comprised of metal cations, N(SO2)2 groups and H2O molecules and the outer regions are formed by the 4‐substituted phenyl rings of the folded anions. In the two‐dimensional coordination networks, the cations adopt either an octahedral [Na(O–S)2(OH2)4] ( 1 , 2 ) or a distorted monocapped octahedral [NaN(O–S)4(OH2)2] ( 3 , 4 ) environment. Taking into account the differing crystal symmetries within the two pairs of compounds, it is remarkable that the trihydrates 1 / 2 and the monohydrates 3 / 4 each display chemically identical and nearly isometric Na–O or Na–O/N networks. In the crystal packings, parallel layers are connected through weak hydrogen bonds C–H…O(nitro) ( 1 ) or C–H…F ( 2 , 3 ), or through short “type I” I…I contacts ( 4 ). There is good evidence that the strikingly distinct crystal symmetries in the halogenated homologues 3 / 4 are determined by the specific complementarity requirements of the interlayer binding centres. 相似文献
Polysulfonylamines. XCIV. Molecules with Unusually Long N(sp2)–Si(sp3) Bonds: Synthesis and Crystal Structures of 1,2-Benzenedisulfonylaminosilanes The following compounds were obtained by metathesis of silver 1,2-benzenedisulfonimide (AgZ) with the appropriate chlorosilanes: ZSiMe3 ( 4 ), ZSinPr3, ZSiMe2nBu, ZSiMe2(CMe2–CHMe2) ( 7 ), (Z)2SiMe2 ( 8 ). In the crystal structures of 4 (monoclinic, space group P21/n), 7 (monoclinic, P21/c) and 8 (monoclinic, P21/n), which were determined by low-temperature X-ray diffraction, the molecules adopt the N-silyl form and display unusually long bonds between the trigonal-planar N and the tetrahedrally coordinated Si atoms ( 4 : 182.6, 7 : 184.1, 8 : 177.8 and 180.5 pm). For 7 in CDCl3 solution, 1H and 13C NMR data indicate N,O-silylotropy. The solid state structures of molecules 4 and 7 strongly suggest that the N–Si bond lengthening in N,N-disulfonylated aminosilanes is mainly induced by the π-acceptor character of the SO2 groups and not by the occasionally observed coordination expansion of the Si atom through short intramolecular O…Si contacts. 相似文献
The title complex, obtained by treating ortho‐benzenedisulfonimide (HZ) with LiOH in aqueous solution, has been characterized by low‐temperature X‐ray diffraction (triclinic, space group P&1macr;, Z' = 1). The lithium cation is bonded to one sulfonyl oxygen atom and three water molecules in a distorted tetrahedral configuration [Li‐O 189.3(3)‐201.2(3) pm, O‐Li‐O 98.5(2)‐123.2(2)?]. The zero‐dimensional [Li(Z)(H2O)3] complexes, which display an intramolecular O(W)‐H···O hydrogen bond, are cross‐linked via five O(W)‐H···O/N/O(W) interactions and a remarkably short C‐H···O bond (H···O 217 pm, C‐H···O 170?) to form a two‐dimensional assembly comprising an internal polar lamella of metal cations, (SO2)2N groups and water molecules, and hydrophobic peripheral regions consisting of protruding benzo groups. In the packing, alternate carbocycles drawn from adjacent layers set up a π‐stacking array of parallel aromatic rings (intercentroid distances 349 and 369 pm, cycle spacings 331 and 336 pm). In a short survey, the currently known crystal packings of seven MIZ · n H2O (n ≥ 0) complexes are examined and compared. 相似文献
Polysulfonylamines. CLIV. Crystal Structures of Metal Di(methanesulfonyl)amides. 7. A Three‐Dimensional Coordination Polymer Built up from Layers and Pillars: Crystal Structure of Ba[(CH3SO2)2N]2·2H2O The barium compound BaA2·2H2O, derived from HA = di(methanesulfonyl)amine, has been characterized by single crystal X‐ray diffraction at —95 °C (monoclinic, space group P21/n, Z = 4). Despite numerous metal‐ligand bonds, the independent anions A— and A′— retain the pseudo‐C2 symmetric conformation that commonly occurs in organic onium salts BH+A—. The large cation attains ninefold coordination via interactions with one (O, N)‐chelating A—, three κ1O‐bonding A—, two κ1O‐bonding A′— and two monodentate water molecules; if a distinctly longer barium‐water distance is included, the coordination number may alternatively be viewed as 9 + 1 and one water molecule regarded as an asymmetrically μ2‐bridging ligand. In contrast to the previously reported layer structures of SrA2 and PbA2, the present crystal displays a three‐dimensional coordination assembly consisting of layers formed by the cations, the water molecules and the pentadentate A— ligands, and of interlayer pillars provided by the bidentate A′— ligands; however, the Ba2+/A— substructure turns out to be topologically and crystallographically congruent with the corresponding M2+/A— substructures in SrA2 and PbA2. The crystal cohesion of the barium complex is reinforced by four O(W)—H···O=S hydrogen bonds and several non‐classical C—H···O=S hydrogen bonds. 相似文献
Polysulfonylamines. CXI. The First X‐Ray Structures of Cationic Diorganyltin(IV) Dichelates [R2Sn(L–L)2]2⊕ Involving Bidentate Phosphine Oxide Ligands: Di(methanesulfonyl)amide as a Non‐Coordinating Counter‐Ion The reaction of Me2Sn(A)2, where A⊖ = (MeSO2)2N⊖, with DPPOE = ethane‐1,2‐diylbis(diphenylphosphine oxide) or CDPPOET = cis‐ethene‐1,2‐diylbis(diphenylphosphine oxide) yields the ionic dichelates [Me2Sn(dppoe)2]2⊕ · 2 A⊖ ( 1 ; monoclinic, space group P21/c) and [Me2Sn(cdppoet)2]2⊕ · 2 A⊖ ( 2 ; monoclinic, P21/n). A solvated variety of 2 , [Me2Sn(cdppoet)2]2⊕ · 2 A⊖ · Et2O · 0.15 MeCN ( 4 ; triclinic, P 1), was serendipitously obtained by thermal degradation of the new compound [Me2Sn(A)(μ‐OH)]2 · 2 CDPPOET in an MeCN/Et2O medium. The crystals of 1 , 2 and 4 consist of discrete formula units (one independent unit for 1 and 2 , two independent units for 4 ); in the structure of 4 , the solvent molecules are located in lattice cavities. All the tin atoms lie on crystallographic inversion centres and display moderately distorted octahedral C2O4 coordinations with short Sn–O bonds in the range 218–223 pm. Within the formula units, the anions are connected to the P–CH donor groups of the chelating ligands by C–H…O/N interactions, some of which are remarkably short (e.g. in 1 : H…O 220 pm, C–H…O 170°; H…N 242 pm, C–H…N 153°). 相似文献
There have been many reports of the surface segregation of minor elements, especially Mg, into surface layers and oxide films on the surface of Al alloys. LM6 casting alloy (Al-12%Si) represents a challenging system to examine such segregation as the alloy features a particularly inhomogeneous phase structure. The very low but mobile Mg content (approximately 0.001 wt.%), and the surface segregation of modifiers such as Na, mean the surface composition responds in a complex manner to thermal treatment conditions. X-ray photoelectron spectroscopy (XPS) has been used to determine the distribution of these elements within the oxide film. Further investigation by dynamic secondary ion mass spectrometry (DSIMS) confirmed a strong alignment of segregated Na and Mg into distinct phases of the structure. 相似文献
Dense micro-cermets made of nickel ferrites and copper micrometric particles were obtained from partial reduction under hydrogenated atmosphere at 350 °C of mixed copper nickel ferrites, and sintering in nitrogen at 980 °C. The small copper particles are homogeneous in size and well dispersed in the spinel oxide matrix. No exudation of copper metal was observed after sintering. The micro-cermets prepared are semi-conducting materials with electrical conductivity lying from 44 to 130 S/cm at 980 °C. Their overall characteristics make them interesting for inert anodes dedicated to aluminium electrolysis in melted cryolite. 相似文献
7‐Chloromethyl‐6‐nitro‐5H‐thiazolo[3,2‐a]pyrimidin‐5‐one ( 2 ) is obtained by cyclocondensation of 2‐aminothiazole with ethyl 4‐chloroacetoacetate. This product was shown to react with various nitronate or malonate anions under microwave irradiation to give potentially bioactive 6‐nitro‐5H‐thiazolo[3,2‐a]pyrimidin‐5‐ones. Extension to other anions centered on S atom allows for the generalization this synthetic procedure. 相似文献
Ionics - This work reports the effect of tantalum (0.1–1 at.% Ta) on the photocatalytic performance of TiO2 annealed at 1373 and 1673 K in air. It was shown that addition of... 相似文献
New non‐fouling tubes are developed and their influence on the adhesion of neuroproteins is studied. Recombinant prion proteins are considered as a single component representative of hydrophobic proteins. Samples are stored for 24 h at 4 °C in tubes coated with two different coatings: poly(N‐isopropylacrylamide) as a hydrophilic surface and a plasma‐fluorinated coating as a hydrophobic one. The protein adhesion is monitored by ELISA tests, XPS and confocal microscopy. It appears that the highest recovery of recombinant prion protein in the liquid phase is obtained with the hydrophilic surface while the hydrophobic character of the storage tube induces an important amount of biological loss. However, the recovery is not complete even for tubes coated with poly(N‐isopropylacrylamide).