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1.
Structures of Ionic Di(arenesulfonyl)amides. 2. Silver(I) Di(arenesulfonyl)amides and a Silver(I) (Arenesulfonyl)(alkanesulfonyl)amide: From Ribbons to Lamellar Layers Exhibiting Short C–H…Hal–C or C–Br…Br–C Interlayer Contacts Low‐temperature X‐ray crystal structures are reported for AgN(SO2C6H4‐4‐X)2 · H2O, where X is Cl ( 4 ) or Br ( 5 ), and for AgN(SO2Ph)(SO2Me) ( 6 ). Compounds 4 and 5 and the previously described F analogue ( 3 ) are isotypic, though not strictly isostructural (monoclinic, space group P21/c, Z = 4, but egregiously large discrepancies of x and z coordinates for corresponding atoms). Throughout this triad, glide‐plane related formula units are linked along the z axis to form infinite ribbons [(ArSO2)2N–Ag(μ‐H2O)], in which Ag extends its coordination number to five by accepting one Ag–O bond from each of the (ArSO2)2N ligands in the adjacent units. By means of O–H…O(S) hydrogen bonds, the ribbons are associated into lamellar layers parallel to the xz plane. Owing to the folded conformation of the anions, the layers display an inner polar region of Ag atoms, H2O molecules and N(SO2)2 groups, outer apolar regions of stacked pairs of aryl rings, and interlayer regions hosting the halogen atoms. Inspection of the latter areas provides sound evidence that the distinct juxtapositions of adjacent layers arise from specific interlamellar attractions and repulsions ( 3 : two C–H…F, all F…F beyond the van der Waals limit dW; 4 : one C–H…Cl, close packing of Cl atoms at Cl…Cl ≈ dW; 5 : one C–H…Br, one short Br…Br contact < dW, all other Br…Br > dW). Structure 6 (monoclinic, P21/n, Z = 4) consists of a lamellar coordination polymer, in which the cation accepts one Ag–N and three Ag–O bonds drawn from four different anions. On account of crystal symmetry, the extended ligand has its Ph and Me groups distributed on both sides of the sheet, the phenyl rings forming the apolar regions of the lamella, whereas the smaller methyl groups are integrated into the corrugated inorganic region by means of weak C–H…O hydrogen bonds.  相似文献   

2.
Structures of Ionic Di(arenesulfonyl)amides. 1. Onium Di(arenesulfonyl)amides: From the Extended to the Folded Conformation of the (ArSO2)2N Anion In a study preceding the investigation of lamellar metal di(arenesulfonyl)amides, the bonding and conformational characteristics of non‐coordinating (ArSO2)2N ions have been established within a series of appropriate onium salts. Starting from the strong NH acids HN(Q‐4‐X)2, where Q = SO2C6H4, the following model compounds were prepared by neutralization or cocrystallization procedures and subjected to low‐temperature X‐ray analyses: Pr4N. N(Q‐4‐COOMe)2 ( 2 , monoclinic, space group C2/c, Z = 4), Pr4N · N(Q‐4‐COOH)2 ( 3 , monoclinic, Cc, Z = 4, O2SNSO2 group disordered), Me3NOH · N(Q‐4‐F)2 ( 4 , monoclinic, P21/n, Z = 4), [DA18C6]2⊕ · 2 N(Q‐4‐H)2 ( 6 , cation = 1,10‐diazonia‐18‐crown‐6, monoclinic, P21/c, Z = 2), [DA18C6]2⊕ · 2 N(Q‐4‐Me)2 ( 7 , triclinic, P1, Z = 1), and [DA18C6]2⊕ · 2 N(Q‐4‐Cl)2 · 2 CH2Cl2 ( 8 , monoclinic, P21/c, Z = 2). Structures 2 – 4 represent the energetically favoured, extended or open conformation of the CO2S–N–SO2C bridge (crystallographic twofold symmetry for 2 , pseudo‐C2 symmetry for 3 and 4 ), whereas in 6 – 8 the anions adopt the folded or hair‐pin conformation (pseudo‐Cs symmetry), which is a prerequisite in lamellar structures. The interdependence of bond lengths and angles within N(SO2C)2 and HN(SO2C)2 moieties is substantiated. In 6 – 8 , the [DA18C6]2⊕ macrocycles exhibit the well‐known “biangular” Ci conformation and are connected to two symmetry related anions by N–H…O hydrogen bonds; structures 4 and 3 respectively display O–H…N bonded cation‐anion pairs or C(O)–O–H…O=S mediated anion chains. Weak hydrogen bonds C–H…O are observed in all the crystal packings. The hitherto unreported amines HN(Q‐4‐X)2, where X is C(O)OMe or C(O)NH2, were obtained by treating the corresponding dicarboxylic acid with OSCl2 to form the bis(acyl chloride) and subjecting the latter to methanolysis or ammonolysis.  相似文献   

3.
Structures of Ionic Di(arenesulfonyl)amides. 4. Cross‐Linking Lamellar Layers by O–H…O Hydrogen Bonds: Structures of MN(SO2C6H4‐4‐COOH)2 (M = K, Rb, Cs) Syntheses and low‐temperature X‐ray crystal structures are reported for MIN(SO2C6H4‐4‐COOH)2, where M = K (monoclinic, space group P21/c, Z = 4, Z′ = 1), M = Rb (monoclinic, P21, Z = 4, Z′ = 2), or M = Cs (monoclinic, P21/c, Z = 4, Z′ = 1). The three compounds are examples of layered inorgano‐organic solids where the inorganic component is comprised of metal cations and N(SO2)2 groups and the outer regions are formed by the 4‐carboxy substituted phenyl rings of the folded anions. In the two‐dimensional coordination networks, K and Cs adopt irregular and chemically distinct [MN1O7] octacoordinations, whereas the independent Rb cations attain irregular nonacoordinations of type [RbN2O7] or [RbO9] respectively. The crystal packings of the compounds are governed by self‐assembly of parallel layers through exhaustive hydrogen bonding between carboxylic acid groups, resulting in a dense array of cyclic (COOH)2 motifs within the interlamellar regions.  相似文献   

4.
Metal Salts of Benzene‐1,2‐di(sulfonyl)amine. 3. Crystal Structures of the Free Protonated Ligand HN(SO2)2C6H4 (= HZ) and the Lamellar Cesium Salt CsZ Benzene‐1,2‐di(sulfonyl)amine ( 1 ; HZ), known since 1921, is a very strong NH acid and readily reacts with aqueous CsCl to form crystalline CsZ ( 3 ). For both compounds, crystal structures were determined by X‐ray diffraction at –100 °C ( 1 : monoclinic, space group P21/n, Z = 4; 3 : orthorhombic, Cmcm, Z = 4). In 1 , the five‐membered 1,3,2‐dithiazole heterocycle possesses an envelope conformation, the N atom lying 29.4(2) pm outside the mean plane of the S–C–C–S moiety [S–N 167.06(15) and 167.53(15) pm, S–N–S 114.57(8)°]. In the crystal, HZ molecules are linked into chains by a conventional N–H…O hydrogen bond and further associated via four weak C–H…O bonds to form a three‐dimensional network. The conjugate Z ion in the layered structure of the salt 3 displays crystallographic C2v symmetry, leading to an ideally planar bicyclic framework [S–N 158.29(15) pm, S–N–S 116.53(17)°]. Each of the five electronegative atoms bridges two cations, Cs attaining a tenfold coordination by forming bonds to two (O,N,O)‐chelating and four κ1O‐monodentate ligands. The Cs–O/N interactions create a polar [CsN(SO2)2] lamella, which is lipophilically wrapped by parallel benzo rings protruding perpendicularly from its surfaces. In contrast to the previously reported lamellar metal di(arenesulfonyl)amides, the aromatic groups pertaining to adjacent layers of 3 are seen to be markedly interlocked.  相似文献   

5.
The adsorption behaviour of the CdII–MOF {[Cd(L)2(ClO4)2]·H2O ( 1 ), where L is 4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole, for butan‐2‐one was investigated in a single‐crystal‐to‐single‐crystal (SCSC) fashion. A new host–guest system that encapsulated butan‐2‐one molecules, namely poly[[bis{μ3‐4‐amino‐3,5‐bis[3‐(pyridin‐4‐yl)phenyl]‐1,2,4‐triazole}cadmium(II)] bis(perchlorate) butanone sesquisolvate], {[Cd(C24H18N6)2](ClO4)2·1.5C4H8O}n, denoted C4H8O@Cd‐MOF ( 2 ), was obtained via an SCSC transformation. MOF 2 crystallizes in the tetragonal space group P43212. The specific binding sites for butan‐2‐one in the host were determined by single‐crystal X‐ray diffraction studies. N—H…O and C—H…O hydrogen‐bonding interactions and C—H…π interactions between the framework, ClO4? anions and guest molecules co‐operatively bind 1.5 butan‐2‐one molecules within the channels. The adsorption behaviour was further evidenced by 1H NMR, IR, TGA and powder X‐ray diffraction experiments, which are consistent with the single‐crystal X‐ray analysis. A 1H NMR experiment demonstrates that the supramolecular interactions between the framework, ClO4? anions and guest molecules in MOF 2 lead to a high butan‐2‐one uptake in the channel.  相似文献   

6.
Alkanolamines have been known for their high CO2 absorption for over 60 years and are used widely in the natural gas industry for reversible CO2 capture. In an attempt to crystallize a salt of (RS)‐2‐(3‐benzoylphenyl)propionic acid with 2‐amino‐2‐methylpropan‐1‐ol, we obtained instead a polymorph (denoted polymorph II) of bis(1‐hydroxy‐2‐methylpropan‐2‐aminium) carbonate, 2C4H12NO+·CO32−, (I), suggesting that the amine group of the former compound captured CO2 from the atmosphere forming the aminium carbonate salt. This new polymorph was characterized by single‐crystal X‐ray diffraction analysis at low temperature (100 K). The salt crystallizes in the monoclinic system (space group C2/c, Z = 4), while a previously reported form of the same salt (denoted polymorph I) crystallizes in the triclinic system (space group P, Z = 2) [Barzagli et al. (2012). ChemSusChem, 5 , 1724–1731]. The asymmetric unit of polymorph II contains one 1‐hydroxy‐2‐methylpropan‐2‐aminium cation and half a carbonate anion, located on a twofold axis, while the asymmetric unit of polymorph I contains two cations and one anion. These polymorphs exhibit similar structural features in their three‐dimensional packing. Indeed, similar layers of an alternating cation–anion–cation neutral structure are observed in their molecular arrangements. Within each layer, carbonate anions and 1‐hydroxy‐2‐methylpropan‐2‐aminium cations form planes bound to each other through N—H…O and O—H…O hydrogen bonds. In both polymorphs, the layers are linked to each other via van der Waals interactions and C—H…O contacts. In polymorph II, a highly directional C—H…O contact (C—H…O = 156°) shows as a hydrogen‐bonding interaction. Periodic theoretical density functional theory (DFT) calculations indicate that both polymorphs present very similar stabilities.  相似文献   

7.
Weak interactions between organic molecules are important in solid‐state structures where the sum of the weaker interactions support the overall three‐dimensional crystal structure. The sp‐C—H…N hydrogen‐bonding interaction is strong enough to promote the deliberate cocrystallization of a series of diynes with a series of dipyridines. It is also possible that a similar series of cocrystals could be formed between molecules containing a terminal alkyne and molecules which contain carbonyl O atoms as the potential hydrogen‐bond acceptor. I now report the crystal structure of two cocrystals that support this hypothesis. The 1:1 cocrystal of 1,4‐diethynylbenzene with 1,3‐diacetylbenzene, C10H6·C10H10O2, (1), and the 1:1 cocrystal of 1,4‐diethynylbenzene with benzene‐1,4‐dicarbaldehyde, C10H6·C8H6O2, (2), are presented. In both cocrystals, a strong nonconventional ethynyl–carbonyl sp‐C—H…O hydrogen bond is observed between the components. In cocrystal (1), the C—H…O hydrogen‐bond angle is 171.8 (16)° and the H…O and C…O hydrogen‐bond distances are 2.200 (19) and 3.139 (2) Å, respectively. In cocrystal (2), the C—H…O hydrogen‐bond angle is 172.5 (16)° and the H…O and C…O hydrogen‐bond distances are 2.25 (2) and 3.203 (2) Å, respectively.  相似文献   

8.
Pale yellow single crystals of [O=C(NPPh3)C(I)=C(NPPh3)‐C(NPPh3)2]+I·1.5 thf ( 1 ·1.5 thf) have been obtained by the reaction of INPPh3 with thallium in thf suspension. They are characterized by IR spectroscopy and by a crystal structure determination. 1 ·1.5 thf crystallizes in the monoclinic space group P21/n, Z = 4, lattice dimensions at ‐83?C: a = 1101.7(1), b = 3449.0(2), c = 2000.4(1) pm, β = 104.88(1)?, R1 = 0.0382. 1 can be understood as a cationic variation of (Z)‐2‐butenale in which all H atoms are substituted by triphenylphosphoraneimine residues and by a iodine atom, respectively.  相似文献   

9.
An unpredicted fourfold screw N—H…O hydrogen bond C(4) motif in a primary dicarboxamide (trans‐cyclohexane‐1,4‐dicarboxamide, C8H14N2O2) was investigated by single‐crystal X‐ray diffraction and IR and Raman spectroscopies. Electron‐density topology and intermolecular energy analyses determined from ab initio calculations were employed to examine the influence of weak C—H…O hydrogen‐bond interactions on the peculiar arrangement of molecules in the tetragonal P43212 space group. In addition, the way in which the co‐operative effects of those weak bonds might modify their relative influence on molecular packing was estimated from cluster calculations. Based on the results, a structural model is proposed which helps to rationalize the unusual fourfold screw molecular arrangement.  相似文献   

10.
The synthesis, 1H and 13C NMR spectra, and X‐ray structures are described for three dialkoxy ethynylnitrobenzenes that differ only in the length of the alkoxy chain, namely 1‐ethynyl‐2‐nitro‐4,5‐dipropoxybenzene, C14H17NO4, 1,2‐dibutoxy‐4‐ethynyl‐5‐nitrobenzene, C16H21NO4, and 1‐ethynyl‐2‐nitro‐4,5‐dipentoxybenzene, C18H25NO4. Despite the subtle changes in molecular structure, the crystal structures of the three compounds display great diversity. Thus, 1‐ethynyl‐2‐nitro‐4,5‐dipropoxybenzene crystallizes in the trigonal crystal system in the space group , with Z = 18, 1,2‐dibutoxy‐4‐ethynyl‐5‐nitrobenzene crystallizes in the monoclinic crystal system in the space group P 21/c , with Z = 4, and 1‐ethynyl‐2‐nitro‐4,5‐dipentoxybenzene crystallizes in the triclinic crystal system in the space group , with Z = 2. The crystal structure of 1‐ethynyl‐2‐nitro‐4,5‐dipropoxybenzene is dominated by planar hexamers formed by a bifurcated alkoxy sp‐C—H…O,O′ interaction, while the structure of the dibutoxy analogue is dominated by planar ribbons of molecules linked by a similar bifurcated alkoxy sp‐C—H…O,O′ interaction. In contrast, the dipentoxy analogue forms ribbons of molecules alternately connected by a self‐complementary sp‐C—H…O2N interaction and a self‐complementary sp2‐C—H…O2N interaction. Disordered solvent was included in the crystals of 1‐ethynyl‐2‐nitro‐4,5‐dipropoxybenzene and its contribution was removed during refinement.  相似文献   

11.
Structures of Ionic Di(arenesulfonyl)amides. 5. Lamellar Layer Structures of M[N(SO2C6H4‐4‐COOCH3)2] · n H2O (M = Na, n = 1; M = K, n = 0): Are there Weak Hydrogen Bonds CH2–H…O=C between the Layers? The new lamellar compounds NaN(SO2C6H4‐4‐COOMe)2 · H2O ( 1 a ) and KN(SO2C6H4‐4‐COOMe)2 ( 2 a ), obtained by neutralizing the corresponding strong NH acid with aqueous NaOH or KOH, were characterized by low‐temperature X‐ray diffraction ( 1 a : orthorhombic, space group Pbca, Z = 8, Z′ = 1; 2 a : orthorhombic, P212121, Z = 8, Z′ = 2). Both crystals are further examples of layered inorgano‐organic solids where the inorganic component is comprised of metal cations, coordinating N(SO2)2 groups and water molecules (in 1 a ) and the outer regions are formed by the 4‐substituted phenyl rings of the folded anions, which approximate to mirror symmetry. In the two‐dimensional networks, the cations adopt respectively a distorted octahedral [Na(O–S)4(OH2)2], an irregular [K(1)O6N2], or an irregular [K(2)O9] coordination. In contrast to the previously reported carboxylic congeners, where an extensive series of C–O–H…O=C hydrogen bonds is observed between layers, the esterified materials do not display any O–CH2–H…O=C interlayer bonding, although such interactions and short Car–H…O=C/O=S contacts exist within the lamellae.  相似文献   

12.
Polysulfonylamines. CLXXXIV. Crystal Structures of Molecular Triphenylphosphanegold(I) Di(4‐X‐benzenesulfonyl)amides: Isomorphism and Close Packing (X = Me, F, Cl, NO2) vs. Structure‐Determining C–X···Au/O Halogen Bonds (X = Br, I) In order to study the structure‐determining influence that halogen bonding can exert during the course of crystallization, solid‐state structures are compared for two previously reported and four new molecular gold(I) complexes of the type Ph3P–Au–N(SO2–C6H4–4‐X)2, each featuring linear P,N coordination at gold and two phenyl rings with varying p‐substituents X = Me, F, Cl, NO2, Br or I. The compounds were synthesized by reactions of Ph3PAuX (X = Cl or I) with the corresponding silver di(arenesulfonyl)amides, crystallized from dichloromethane, and characterized by low‐temperature X‐ray diffraction. The Me, F, Cl and NO2 congeners are isomorphic and crystallize without solvent inclusion in the chiral orthorhombic space group P212121 (Z′ = 1). These structures are governed by isotropic close packing via three‐dimensional 21 symmetry, incidentally supported by an invariant set of C–H···O=S hydrogen bonds, CH/π interactions and π/π stackings of aromatic rings; in particular, the hard halogen atoms of the fluoro and the chloro homologues are not involved in X···Au, X···O or X···X interactions. The higher homologues, with soft halogen atoms, were obtained as a dichloromethane hemisolvate for X = Br and a corresponding monosolvate for X = I, each triclinic in the centrosymmetric space group (Z′ = 1). Here, the primary structural effect is implemented by infinite chains in which translation‐related molecules are connected for the bromo compound by a bifurcated Au···Br(2)···O=S interaction, for the iodo congener by an equivalent Au···I(2)···O=S interaction and a short halogen bond C–I(1)···O=S. The latter bond is stronger than a similar C–Br···O=S interaction and induces a conformational adjustment of the (CSO2)2N group from the normal twofold symmetry in the bromo compound to an energetically unfavourable asymmetric form in the iodo homologue. In both cases, pairs of antiparallel molecular catemers are associated into strands via sixfold phenyl embraces, the strands are stacked to form layers, the solvent molecules are intercalated between adjacent layers, and the crystal packings are reinforced by a number of C–H···O=S hydrogen bonds and interactions of aromatic rings.  相似文献   

13.
Structures of Ionic Di(arenesulfonyl)amides. 8. Sodium Bis[di(4‐fluorobenzenesulfonyl)amido‐N]argentate: A Heterobimetallic Complex Exhibiting a Lamellar Layer Structure and Short C–H···F–C Interlayer Contacts Na[Ag{N(SO2–C6H4–4‐F)2}2] (monoclinic, C2/c, Z′ = 1/2) is the first heterobimetallic representative in a well‐documented class of layered inorgano‐organic solids where the inorganic component is comprised of metal cations and coordinating N(SO2)2 groups and the outer regions are formed by the aromatic rings of the di(arenesulfonyl)amide entities, which adopt a folded conformation approximating to mirror symmetry. The inversion‐symmetric bis(amido)argentate unit of the novel compound displays an exactly linear N–Ag–N core and short Ag–N bonds of 217.55(17) pm (at ?140 °C); the coordination number of the silver ion is extended to 2 + 6 by four internal and two external Ag···O secondary interactions. The polar lamella is constructed from rows of Na+ ions located on twofold axes, alternating with bis(amido)argentate strands reinforced by Ag···O interactions and weak C–H···O hydrogen bonds; Na+ is embedded in an O6 environment. Adjacent layers are cross‐linked via short C–H···F–C contacts suggestive of weak hydrogen bonding enhanced by cooperativity.  相似文献   

14.
Structures of Ionic Di(arenesulfonyl)amides. 6. Limits to the Formation of Lamellar Metal Di(arenesulfonyl)amides: Three Lithium Complexes and One Cadmium Complex According to low‐temperature X‐ray studies, the new compounds LiN(SO2C6H4‐4‐X)2 · 2 H2O, where X = COOH ( 1 ) or COOMe ( 2 ), LiN(SO2C6H4‐4‐CONH2)2 · 4 H2O ( 3 ), and Cd[N(SO2C6H4‐4‐COOH)2]2 · 8 H2O ( 4 ) crystallize in the triclinic space group P1 ( 1 – 3 : Z′ = 1; 4 : Z′ = 1/2, Cd2+ on an inversion centre) and display almost perfectly folded anions approximating to mirror symmetry. The lithium ions in 1 – 3 have distorted tetrahedral environments respectively set up by two O=S groups drawn from different anions and two water molecules, two O=S groups of a chelating anion and two water molecules, or one O=C group and three water ligands, whereas the cation of 4 is fully hydrated to form an octahedral [Cd(H2O)6]2+ complex. The structure refinements for 3 and 4 were marred by positional disorder of the non‐coordinating N(SO2)2 moieties. Compounds 1 and 4 extend a previously described series of lamellar metal di(arenesulfonyl)amides where the two‐dimensional inorganic component is comprised of cations, N(SO2)2 groups and water molecules and the outer regions are formed by the 4‐substituted phenyl rings. Both crystal packings are governed by self‐assembly of parallel layers through exhaustive hydrogen bonding between carboxylic groups, and there is good evidence that the labile inorganic networks, generated via Li–O and hydrogen bonds in 1 or solely hydrogen bonds in 4 , are efficiently stabilized by the strong cyclic (COOH)2 motifs within the interlayer regions. In the absence of these, the lamellar architecture is seen to collapse in 2 and 3 , where the carboxyl groups are replaced by methoxycarbonyl or carbamoyl functions and the inorganic components are segregated in parallel tunnels pervading the anion lattices.  相似文献   

15.
The asymmetric unit of O,O′‐dimethyl [(2,3,4,5,6‐pentafluorophenyl)hydrazinyl]phosphonate, C8H8F5N2O3P, is composed of two symmetry‐independent molecules with significant differences in the orientations of the C6F5 and OMe groups. In the crystal structure, a one‐dimensional assembly is mediated from classical N—H…O hydrogen bonds, which includes R22(8), D(2) and some higher‐order graph‐set motifs. By also considering weak C—H…O=P and C—H…O—C intermolecular interactions, a two‐dimensional network extends along the ab plane. The strengths of the hydrogen bonds were evaluated using quantum chemical calculations with the GAUSSIAN09 software package at the B3LYP/6‐311G(d,p) level of theory. The LP(O) to σ*(NH) and σ*(CH) charge‐transfer interactions were examined according to second‐order perturbation theory in natural bond orbital (NBO) methodology. The hydrogen‐bonded clusters of molecules, including N—H…O and C—H…O interactions, were constructed as input files for the calculations and the strengths of the hydrogen bonds are as follows: N—H…O [R22(8)] > N—H…O [D(2)] > C—H…O. The decomposed fingerprint plots show that the contribution portions of the F…H/H…F contacts in both molecules are the largest.  相似文献   

16.
Polysulfonylamines. CXXIV. Preparation of Organylmercury(II) Di(methanesulfonyl)amides and Crystal Structure of Ph–Hg–N(SO2Me)2 Four N,N‐disulfonylated organylmercury(II) amides R–Hg–N(SO2Me)2, where R is Me, iPr, Me3SiCH2 or Ph, were obtained on treating the appropriate chlorides RHgCl with AgN(SO2Me)2, and characterized by 1H and 13C NMR spectra. In the crystal structure of the phenyl compound (orthorhombic, space group Pbca, Z = 8, X‐ray diffraction at –95 °C), the molecule exhibits a covalent and significantly bent C–Hg–N grouping [bond angle 172.7(3)°; Hg–C 204.0(8), Hg–N 209.1(7) pm]. One sulfonyl oxygen atom forms a short intramolecular Hg…O contact [296.1(5) pm] and simultaneously catenates glide‐plane related molecules via a second Hg…O interaction 297.6(5) pm], thus conferring upon HgII the effective coordination number 4 and a geometrically irregular coordination polyhedron (bond angles from 173 to 54°).  相似文献   

17.
Metal Salts of Benzene‐1,2‐di(sulfonyl)amine. 4. Hydrophobically Wrapped Two‐Dimensional Polymers: Crystal Structures of the Isostructural Metal Complexes [M{C6H4(SO2)2N}(H2O)] (M = K, Rb) and of the Structurally Related Ammonium Salt [(NH4){C6H4(SO2)2N}(H2O)] The previously unreported compounds KZ · H2O ( 1 ), RbZ · H2O ( 2 ) and NH4Z · H2O ( 3 ), where Z is Ndeprotonated ortho‐benzenedisulfonimide, are examples of layered inorgano‐organic solids, in which the inorganic component is comprised of metal or ammonium cations, N(SO2)2 groups and water molecules and the outer regions are formed by the planar benzo rings of the anions. The metal complexes 1 and 2 were found to be strictly isostructural, whereas 3 is structurally related to them by a non‐crystallographic mirror plane ( 1 – 3 : monoclinic, space group P21/c, Z = 4; single crystal X‐ray diffraction at low temperatures). In each structure, the five‐membered 1,3,2‐dithiazolide heterocycle possesses an envelope conformation, the N atom lying about 40 pm outside the mean plane of the S–C–C–S moiety. The metal complexes feature two‐dimensional coordination networks interwoven with O–H…O hydrogen bonds originating from the water molecules. The metal centres adopt an irregular nonacoordination formed by five sulfonyl O atoms, two N atoms and two μ2‐bridging water molecules; each M+ is connected to four different anions. When NH4+ is substituted for M+, the metal–ligand bonds are replaced by N+–H…O hydrogen bonds, but the general topology of the lamella is not affected. In the three structures, the lipophilic benzo groups protrude obliquely from the surfaces of the polar lamellae and display marked interlocking between adjacent layers.  相似文献   

18.
Accurate, low-temperature (81 K) X-ray analyses have been made for two crystalline modifications of the tricyclic orthoamide 1b : a cubic trihydrate in space group Pa3 (Z = 8), where the molecule has crystallographic threefold rotation symmetry, and an anhydrous monoclinic form in space group P21/c (Z = 8) where two symmetry-independent molecules have different configurations, one ail-trans. (as in the cubic trihydrate), the other cis, cis, trans. In the cubic trihydrate, each orthoamide molecule is attached to a triad of H2o molecules by OH…?N H-bonds. A remarkable feature of this structure is the nearly eclipsed conformation about the central C-CH3 bond. In the anhydrous crystal, both types of molecule have the normal staggered orientation of their Me groups. The reversal of the Me orientation in the trihydrate is attributed to C? H…?O H-bonding, which must be much stronger and more directionally specific than has been previously assumed.  相似文献   

19.
Three polymorphs of barium dihydrogen‐hypodiphosphate(IV)‐dihydrate, BaH2P2O6 · 2H2O ( A , B and C ), were obtained and structurally characterized by single‐crystal X‐ray diffraction. A crystallizes in the monoclinic space group P21/n (no. 14) with a = 7.459(1) Å, b = 8.066(1) Å, c = 12.460(2) Å, β = 91.27(1) ° and Z = 4. B crystallizes in the monoclinic space group C2/c (no. 15) with a = 11.049(8) Å, b = 6.486(3) Å, c = 10.956(6) Å, β = 106.89(5) ° and Z = 4. C crystallizes in the orthorhombic space group C2221 (no. 20) with a = 9.193(3) Å, b = 6.199(2) Å, c = 12.888(4) Å and Z = 4. Discrete [H2P2O6]2– units, barium cations and water molecules, held together by intermolecular hydrogen bonds of the type O–H ··· O, build up the structures of the three polymorphs. The phase purity of A and C was verified by powder diffraction measurements.  相似文献   

20.
In solid‐state engineering, cocrystallization is a strategy actively pursued for pharmaceuticals. Two 1:1 cocrystals of 5‐fluorouracil (5FU; systematic name: 5‐fluoro‐1,3‐dihydropyrimidine‐2,4‐dione), namely 5‐fluorouracil–5‐bromothiophene‐2‐carboxylic acid (1/1), C5H3BrO2S·C4H3FN2O2, (I), and 5‐fluorouracil–thiophene‐2‐carboxylic acid (1/1), C4H3FN2O2·C5H4O2S, (II), have been synthesized and characterized by single‐crystal X‐ray diffraction studies. In both cocrystals, carboxylic acid molecules are linked through an acid–acid R 22(8) homosynthon (O—H…O) to form a carboxylic acid dimer and 5FU molecules are connected through two types of base pairs [homosynthon, R 22(8) motif] via a pair of N—H…O hydrogen bonds. The crystal structures are further stabilized by C—H…O interactions in (II) and C—Br…O interactions in (I). In both crystal structures, π–π stacking and C—F…π interactions are also observed.  相似文献   

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