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1.
2.
The bonding geometry of sulfur in the cations of the title compounds, C8H11S+·CF3SO3? and C13H13S+·CF3SO3?, respectively, is similar and is independent of the ratio of the Me/Ph substituents. As expected, in both cations, the S—Ph bonds are somewhat shorter than the S—Me bonds. In both crystal structures, the interaction between cations and anions is similar.  相似文献   

3.
In the title compound, [Sb(CH3)(C6H5)3]BF4, there are four independent cations and anions in the asymmetric unit. The geometry around the Sb atom is distorted tetrahedral, with Sb—C distances in the range 2.077 (4)–2.099 (10) Å and angles at the Sb atom in the range 103.3 (3)–119.0 (4)°.  相似文献   

4.
The molecular structures of the title compounds, 2,4,6‐tri­chloro­phenyl­iso­nitrile (IUPAC name: 2,4,6‐tri­chloro­phenyl isocyanide), C7H2Cl3N, and 2,4,6‐tri­chloro­benzo­nitrile, C7H2Cl3N, are normal. The two structures are not isomorphous, but do contain similar two‐dimensional layers in which pairs of mol­ecules are held together by pairs of Cl?CN [3.245 (3) Å] or Cl?NC [3.153 (2) Å] interactions. The two‐dimensional isomorphism is lost through different layer‐stacking modes.  相似文献   

5.
The cationic part of the homodifunctional amino­phospho­ranyl ligand, C41H41N2P2+·I?, shows interesting features associated with the N—P—C—P—N skeleton. The P—C(H) bond distances [1.696 (3) and 1.697 (3) Å] possess partial double‐bond characteristics. The nature of the P—C(H) and P—N bonds suggests that the positive charge is only distributed around the P—C—P atoms. The structure has near twofold symmetry through the central methyl­ide‐C atom.  相似文献   

6.
Ethyl­tri­phenyl­phospho­nium perrhenate, (C20H20P)[ReO4], and (iodo­methyl)­tri­phenyl­phospho­nium perrhenate, (C19H17IP)[ReO4], have been crystallized from 2‐propanol. Both crystal structures consist of phospho­nium cations and perrhenate anions. The cations show the typical propeller‐like geometry. In both crystals, the positions of the nearly tetrahedral anions are stabilized by weak C—H⋯O hydrogen bonds, and for the latter compound, I⋯π interactions also occur.  相似文献   

7.
8.
In 2,4‐di­hydroxy­benz­aldehyde 2,4‐di­nitro­phenyl­hydrazone N,N‐di­methyl­form­amide solvate {or 4‐[(2,4‐di­nitro­phenyl)­hydrazono­methyl]­benzene‐1,3‐diol N,N‐di­methyl­form­amide solvate}, C13H10N4O6·C3H7NO, (X), 2,4‐di­hydroxy­aceto­phenone 2,4‐di­nitro­phenyl­hydrazone N,N‐di­methyl­form­am­ide solvate (or 4‐{1‐[(2,4‐di­nitro­phenyl)hydrazono]ethyl}benzene‐1,3‐diol N,N‐di­methyl­form­amide solvate), C14H12N4O6·C3H7NO, (XI), and 2,4‐di­hydroxy­benzo­phenone 2,4‐di­nitro­phenyl­hydrazone N,N‐di­methyl­acet­amide solvate (or 4‐­{[(2,4‐di­nitro­phenyl)hydrazono]phenyl­methyl}benzene‐1,3‐diol N,N‐di­methyl­acet­amide solvate), C19H14N4O6·C4H9NO, (XII), the molecules all lack a center of symmetry, crystallize in centrosymmetric space groups and have been observed to exhibit non‐linear optical activity. In each case, the hydrazone skeleton is fairly planar, facilitated by the presence of two intramolecular hydrogen bonds and some partial N—N double‐bond character. Each molecule is hydrogen bonded to one solvent mol­ecule.  相似文献   

9.
Phase equilibria in the LiF-LiCl-LiVO3-Li2SO4-Li2MoO4 system have been studied by differential thermal analysis. The eutectic composition has been determined as follows (mol %): LiF, 17.4; LiCl, 42.0; LiVO3, 17.4; Li2SO4, 11.6; and Li2MoO4, 11.6, with the melting temperature equal to 363°C and the enthalpy of melting equal to (284 ± 7) kJ/kg.  相似文献   

10.
The crystal structure of the title compound, alternatively called 3‐[4‐(benzyl­oxy)­phenyl]‐2‐(Ntert‐butoxy­car­bonyl‐N‐methyl­amino)­propi­onic acid, C22H27NO5, has been studied in order to ex­amine the role of N‐methyl­ation as a determinant of peptide conformation. The conformation of the tert‐butoxy­carbonyl group is transtrans. The side chain has a folded conformation and the two phenyl rings are effectively perpendicular to one another. The carboxyl­ate hydroxyl group and the urethane carbonyl group form a strong intermolecular O—H?O hydrogen bond.  相似文献   

11.
At 160 K, the gluco­pyran­osyl ring of the title compound, C20H28ClIO13, has a near‐ideal 4C1 conformation and the fructo­furan­osyl ring has a twist 4T3 conformation. The two hydroxy groups are involved in intra‐ and intermolecular hydrogen bonds, with the latter interactions linking the mol­ecules into infinite one‐dimensional chains. The absolute configuration of the mol­ecule has been determined.  相似文献   

12.
The molecular structures of the title compounds, C25H46N6 and C15H30N6, respectively, show the two guanidyl moieties each connected by propyl bridges. The different substitution pattern of the guanidyl groups has no influence on the distinct localization of their C=N double bonds. Both compounds exhibit approximate twofold symmetry and the crystal packing shows no prominent hydrogen‐bonding interactions.  相似文献   

13.
The structure of the title compound, (C5H12N)4[V10O26(CH3O)2], reveals the presence of four protonated piperidin­ium cations and a [{V10O26}(OCH3)2]4− polyanion having an embedded centre of inversion. The compound is distinguished by presenting, in contrast with other anionic deca­vanadates, two meth­oxy groups bridging the outermost V atoms, and it becomes the first example of this type among reported deca­vanadates.  相似文献   

14.
The title compound, poly­[[di­aqua­di­bromo­cadmium‐μ‐(1,3,5,7‐tetra­aza­tri­cyclo[3.3.1.13,7]decane‐N1:N5)‐aqua­cad­mium‐di‐μ‐bromo‐aqua­cadmium‐μ‐(1,3,5,7‐tetra­aza­tri­cyclo[3.3.1.13,7]decane‐N1:N5)‐di‐μ‐bromo] dihydrate], [Cd3­Br6­(C6­H12­N4)2­(H2O)4]·­2H2O, is made up of two‐dimensional neutral rectangular coordination layers. Each rectangular subunit is enclosed by a pair of Cd32‐Br)6(H2O)3 fragments and a pair of (μ2‐hmt)Cd(H2O)2Br22‐hmt) fragments as sides (hmt is hexa­methyl­enetetr­amine). The unique CdII atom in the Cd2Br2 ring in the Cd32‐Br)6(H2O)3 fragment is in a slightly distorted octahedral CdNOBr4 geometry, surrounded by one hmt ligand [2.433 (5) Å], one aqua ligand [2.273 (4) Å] and four Br atoms [2.6409 (11)–3.0270 (14) Å]. The CdII atom in the (μ2‐hmt)Cd(H2O)2Br22‐hmt) fragment lies on an inversion center and is in a highly distorted octahedral CdN2O2Br2 geometry, surrounded by two trans‐related N atoms of two hmt ligands [2.479 (5) Å], two trans‐related aqua ligands [2.294 (4) Å] and two trans‐related Br atoms [2.6755 (12) Å]. Adjacent two‐dimensional coordination sheets are connected into a three‐dimensional network by hydrogen bonds involving lattice water mol­ecules, and the aqua, bromo and hmt ligands belonging to different layers.  相似文献   

15.
The crystal structure of the title compound, C20H17NO4S, (I), was determined in order to compare the solution and solid‐state conformations. The mol­ecule was synthesized as a building block for incorporation into oligosaccharides comprised of conformationally restricted furan­ose residues. The furan­ose ring adopts an envelope conformation with the ring O atom displaced above the plane (an OE conformation). The pseudorotational phase angle (P) is 88.6° and the puckering amplitude (τm) is 31.5°. The C2—C1—S—C(Ph) torsion angle is ?163.2 (2)°, which places the aglycone in the exo‐anomeric effect preferred position. The C1—S—C14 bond angle is 99.02 (13)° and the plane of the cresyl moiety is oriented nearly parallel to the four in‐plane atoms of the furan­ose ring envelope. The orientation about the C4—C5 bond is gauchegauche [Bock & Duus (1994). J. Carbohydr. Chem. 13 , 513–543].  相似文献   

16.
The four-component system LiF-K2WO4-CaF2-BaWO4 has been studied for the first time using physicochemical methods. The a priori prediction of the phase complex revealed the phase tree and crystallization path of the system. The prediction was verified experimentally, by construction of a topologic model of the phase diagram, and the solution of the equations of the general law of liquidus-surface formation. The density has been measured, and the heat-storage properties of eutectic mixtures have been estimated.  相似文献   

17.
This is the first study of the NaBO2-Na2CO3-Na2MoO4-Na2WO4 quaternary system by differential thermal analysis. Na2[MoO4(x)WO4(1 − x)] solid solutions in the quaternary system are found to not decompose.  相似文献   

18.
Phase equilibria in the three-component systems LiBr-LiVO3-Li2MoO4 and LiBr-Li2SO4-Li2MoO4 have been studied using differential thermal analysis (DTA). Eutectic compositions have been determined (mol %): in the system LiBr-LiVO3-Li2MoO4, 56.0 LiBr, 22.0 LiVO3, and 22.0 Li2MoO4 with a melting temperature of 413°C; and in the system LiBr-Li2SO4-Li2MoO4, 65.0 LiBr, 14.0 Li2SO4, and 21.0 Li2MoO4 with a melting temperature of 421°C. Phase fields have been demarcated.  相似文献   

19.
A series of twist linear tetranuclear 3d–4f Co 2 III Ln 2 III [Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5)] complexes have been prepared under solvothermal conditions and structurally characterized with Schiff-base ligand 2-(((2-hydroxy-3-methoxyphenyl)methylene)amino)-2-(hydroxymethyl)-1,3-propanediol (H4L). The two central Co ions are linked by two alkoxyl oxygen atoms, and one Ln ion lying above and the other below the Co–Co dimer, form a twist linear array. The magnetic susceptibility studies reveal antiferromagnetic or ferromagnetic behaviour, whilst dynamic magnetic studies indicate no slow magnetic relaxation for these complexes.  相似文献   

20.
Two related compounds containing ptert‐butyl‐o‐methyl­ene‐linked phenol or phenol‐derived subunits are described, namely 5,5′‐di‐tert‐butyl‐2,2′‐di­hydroxy‐3,3′‐methyl­ene­di­benz­aldehyde, C23H28O4, (I), and 6,6′‐di‐tert‐butyl‐8,8′‐methyl­ene­bis­(spiro­[4H‐1,3‐benzo­di­oxin‐2,1′‐cyclo­hexane]), C35H48O4, (II). Both compounds adopt a `butterfly' shape, with the two phenol or phenol‐derived O atoms in distal positions. Phenol and aldehyde groups in (I) are involved in intramolecular hydrogen bonds and the two dioxin rings in (II) are in distorted half‐chair conformations.  相似文献   

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